Multi-qubit control using acousto-optic modulators

Abstract

Aspects of the present invention describe techniques for controlling the quantum state of ions in an ion chain for quantum operations. For example, a method is described, comprising: providing a global light beam to ions in the ion chain from a first direction; and providing a corresponding addressing light beam to each ion in a subset of ions in the ion chain from a second direction different from the first direction. The method also includes: dynamically controlling each provided addressing light beam using a corresponding channel in a multi-channel acousto-optic modulator (AOM) to implement one or more quantum gates in a sequence of quantum gates for quantum operations using the ion chain. A quantum information processing (QIP) system including a multi-channel AOM for performing the method is also described.

Description

Technical Field

[0001] This patent application claims priority to U.S. Non-Provisional Application No. 16 / 514099, filed on July 17, 2019, entitled “MULTI-QUIBIT CONTROLWITH ACOUSTO-OPTIC MODULATORS,” and U.S. Provisional Patent Application No. 62 / 701128, filed on July 20, 2018, entitled “MULTI-QUBIT CONTROL WITH ACOUSTO-OPTIC MODULATORS,” the contents of which are incorporated herein by reference in their entirety.

[0002] Government licensing rights

[0003] This invention was made with government support under IARPA Award No. W911NF1610082. The government has certain rights in this invention. Background Art

[0004] Aspects of the present disclosure generally relate to controlling the state of quantum bits (qubits) using counter-propagating light beams.

[0005] Trapped atoms are one of the important ways to implement quantum information processing. Atom-based qubits can be used as quantum memories, quantum gates in quantum computers and simulators, and can be used as nodes in quantum communication networks. Qubits based on trapped atomic ions have a rare combination of properties. For example, qubits based on trapped atomic ions have very good coherence properties, can be prepared and measured with an efficiency close to 100%, and are easily entangled with each other by modulating their Coulomb interactions using suitable external control fields (such as light fields or microwave fields). These properties make atom-based qubits attractive for extended quantum operations, such as quantum computing or quantum simulation that may potentially have longer sequences of quantum circuits or quantum gates.

[0006] The accuracy of the state or information in atom-based qubits is important to avoid systematic errors that can accumulate during quantum operations, and therefore it is desirable to develop techniques to correct or adjust for these types of errors to reduce or eliminate their effects. Summary of the invention

[0007] A brief summary of one or more aspects is given below to provide a basic understanding of these aspects. This summary is not an extensive overview of all aspects considered, and is neither intended to identify key or important elements of all aspects, nor to detail the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to a more detailed description that is given later.

[0008] Quantum information processors or quantum information processing (QIP) systems based on multiple trapped ions (e.g., atomic qubits or qubits) may require independent control of each ion to achieve the flexibility of executing a complete set of universal quantum gates with significantly low overhead. Trapped atoms / ions can be manipulated using Raman transitions, where the beats between two Raman beams (e.g., laser beams or light beams) can coherently drive the state of the internal qubit. In order to control each trapped ion in a processor (e.g., in an ion trap for processing quantum operations), an array of such Raman beams is used, where each beam addresses a single ion. The phase, frequency, and / or amplitude of these Raman beams can be controlled using a multi-channel acousto-optic modulator (AOM) to achieve independent universal control of each atomic qubit.

[0009] One aspect of the present disclosure provides a method for controlling the quantum state of ions in an ion chain for quantum operations. The method includes: providing a global light beam to the ions in the ion chain from a first direction; providing a corresponding addressing light beam to each ion in a subgroup of ions in the ion chain from a second direction opposite to the first direction; and dynamically controlling each of the provided addressing light beams using a corresponding channel in a multi-channel acousto-optic modulator (AOM) to implement one or more quantum gates in a quantum gate sequence of quantum operations using the ion chain.

[0010] Another aspect of the present disclosure is a quantum information processing (QIP) system that controls the quantum state of ions in an ion chain for quantum operations. The QIP includes: a trap configured to implement the ion chain; a first light source configured to provide a global light beam to the ions in the ion chain from a first direction; a set of second light sources configured to provide a corresponding addressing light beam to each ion in a subset of ions in the ion chain from a second direction opposite to the first direction; a multi-channel acousto-optic modulator (AOM); and an optical controller configured to dynamically control the set of second light sources to control each of the provided addressing light beams by using corresponding channels in the multi-channel AOM to implement one or more quantum gates in a sequence of quantum gates for the ion operation using the ion chain.

[0011] Yet another aspect of the present disclosure describes a computer-readable storage medium storing code having instructions executable by a processor for controlling quantum states of ions in an ion chain for quantum operations.

[0012] To accomplish the above and related ends, the one or more aspects include the features fully described below and particularly pointed out in the claims. The following description and the accompanying drawings set forth in detail certain illustrative features of the one or more aspects. However, these features are indicative of only a few of the various ways in which the principles of the various aspects may be employed, and this description is intended to include all such aspects and their equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The disclosed aspects will hereinafter be described in conjunction with the accompanying drawings, which are provided for the purpose of illustrating rather than limiting the disclosed aspects, wherein like reference numerals denote like elements.

[0014] Figure 1A A diagram showing a vacuum chamber housing electrodes for trapping atomic ions in a linear crystal in accordance with aspects of the present disclosure is shown.

[0015] Figure 1B is a diagram illustrating an example of a simplified energy level diagram according to aspects of the present disclosure, the diagram showing laser radiation applied for state initialization.

[0016] Figure 1C is a diagram illustrating an example of a simplified energy level diagram in accordance with aspects of the present disclosure, showing laser radiation applied for detecting qubit states by fluorescence.

[0017] Figure 2A is a diagram illustrating an example of the geometry of a Raman beam in accordance with aspects of the present disclosure.

[0018] Figure 2B is a diagram showing an energy level diagram illustrating coherent stimulated Raman transitions of coupled qubit states in accordance with aspects of the present disclosure.

[0019] Figure 3 is a diagram illustrating an example of a multi-channel acousto-optic modulator (AOM) for multi-qubit control based on aspects of the present disclosure.

[0020] Figure 4 is a diagram illustrating an example of a multi-tone Raman beam alignment system based on aspects of the present disclosure.

[0021] Figure 5 is a diagram illustrating an example of a gate sequence with three qubits in accordance with aspects of the present disclosure.

[0022] Figure 6is a diagram illustrating an example of a computer device based on aspects of the present disclosure.

[0023] Fig. 7A is a block diagram illustrating an example of a quantum information processing (QIP) system based on aspects of the present disclosure.

[0024] Figure 7B is a block diagram illustrating an example of an optical controller based on aspects of the present disclosure.

[0025] Figure 8 is a flow chart illustrating an example of a method based on aspects of the present disclosure. DETAILED DESCRIPTION

[0026] The following detailed description in conjunction with the accompanying drawings is intended to describe various configurations, rather than to represent the only configuration that can implement the concepts described herein. In order to provide a thorough understanding of the various concepts, this detailed description includes specific details. However, it will be apparent to those skilled in the art that these concepts can be implemented without these specific details. In some cases, well-known components are represented in block diagram form to avoid confusion between these concepts.

[0027] As described above, trapped atoms can be used to implement quantum information processing methods and systems. Atom-based qubits can be used as different types of devices, including but not limited to quantum memories, quantum gates, and nodes of quantum communication networks in quantum computers and simulators. Qubits based on trapped atomic ions can have very good coherence properties, can be prepared and measured with an efficiency close to 100%, and can be easily entangled with each other by modulating their Coulomb interactions using a suitable external control field (such as a light field or a microwave field). As used in this disclosure, the terms "atomic ions", "atoms" and "ions" can be used interchangeably to describe particles that will be confined or actually confined in a trap to form a crystal or a similar arrangement or configuration. The present disclosure describes a method or process for controlling the operation of qubits within a crystal of trapped atomic ions using a laser beam, as well as a technique in the form of an apparatus or instrument. Specifically, the present disclosure describes the use of a propagating laser beam, a global beam, and one or more individual beams to control the state of one or more qubits.

[0028] The geometry or structure of a typical ion trap used for quantum information and metrology purposes is a linear radio frequency (RF) Paul trap (also called an RF trap or simply a Paul trap), in which adjacent electrodes possess static and dynamic potentials, resulting in effective inhomogeneous harmonic confinement of ions. An RF Paul trap is a type of trap that uses an electric field to imprison or confine charged particles in a specific area, position, or location. When atomic ions in such a trap are laser-cooled to very low temperatures, the atomic ions form a stable crystal of qubits (e.g., a structured arrangement of qubits), with Coulomb repulsion balancing the external confinement forces. In order to obtain sufficient anisotropy of the trap, the ions can form a linear crystal along the direction of weakening of the confinement, which is an arrangement commonly used in quantum information and metrology applications.

[0029] As required for implementing a specific quantum gate using ions, it may be necessary to address each ion individually to control the phase, frequency, and / or amplitude, and / or polarization. A single global beam can be applied or provided to all ions in an ion chain (e.g., a chain of ions in an ion trap) to control the ions, while also applying or providing individual beams to those ions that perform or implement the quantum gate. These counter-propagating beams, known as Raman optical beams or simply Raman beams, are typically laser beams with very high center frequencies (e.g., 850 THz). However, these beams have a well-defined frequency difference that produces a beat (e.g., 12.6 GHz), which is used as a qubit frequency. A radio frequency (RF) signal is used to control the frequency or phase of the beat produced by the beam, and the beat is then used to drive the qubits (e.g., atomic or ion qubits) in the ion chain. This type of control has previously been achieved by using a single global beam as a means of adjusting the frequency or phase of the beat, but this approach has some limitations.

[0030] For example, when a quantum gate is implemented using only a few ions in an ion chain, because the global beam generates unwanted residual quantum operations, the global beam still irradiates the remaining ions (those ions not used for the quantum gate), resulting in errors (e.g., systematic errors) in those ions that are irradiated by the global beam but not used. An example of such a residual operation is an energy shift or optical shift (e.g., AC Stark shift) that tends to change or shift the phase of a qubit. Therefore, when a quantum algorithm or quantum operation that implements multiple quantum gates in sequence (e.g., a stack of a combination of a single-qubit gate and a double-qubit or 2-qubit gate) is run, the errors generated in individual ions are accumulated in the quantum algorithm or operation.

[0031] However, many of these systematic errors can be tracked or monitored. For example, the 2 qubit energy levels in each ion are internal atomic states where the energy separation is well defined. Therefore, each ion evolves at a known frequency. When an ion has different energies (e.g., caused by light offsets), it evolves at different frequencies. By knowing the frequency at which each ion evolves, it is possible to monitor or track the corresponding phase, because there is always free rotation on the ion, and therefore frequency and phase are related. Therefore, as long as the system (e.g., an experimental clock in the system) is configured to track the clock or duty cycle of an ion (e.g., an atomic qubit), it is possible to monitor or track the phase of the ion even as it shifts over time.

[0032] The errors (e.g., phase shifts or phase errors) caused by the above-mentioned residual operations may be different for each ion in the ion chain. Therefore, these errors need to be corrected individually for each ion. When the control of the ions is limited to the use of a single global beam for this purpose, as in previous systems, these errors cannot be corrected individually because there is no mechanism for individual correction of the ions. In addition, these frequency (and phase) shifts tend to accumulate over time to a point where they may be difficult to correct even if the systematic errors are known. Therefore, these errors need to be corrected not only for each individual ion, but also dynamically as the quantum operation or quantum algorithm progresses.

[0033] In view of the above problems, a quantum information processing (QIP) system based on multiple trapped ions may need to independently control the state of each trapped ion to achieve the flexibility of executing logic with low overhead. The state of the trapped ion can be controlled using Raman transitions, where the beats between two Raman beams can be used to coherently drive the internal quantum bit state. In order to control individual trapped ions in a QIP system, an array of Raman beams is required to provide an individual addressing beam for each single trapped ion. By using a multi-channel acousto-optic modulator (AOM), each individual addressing beam can be controlled, thereby having the ability to individually correct any systematic errors accumulated by the trapped ions. It should be understood that although a multi-channel AOM is described herein for individual trapped ion control, the present disclosure is not limited to this, and a multi-channel AOM can also be implemented using multiple single-channel AOMs or multiple smaller multi-channel AOMs.

[0034] In some aspects of the present disclosure, a multi-channel AOM may include multiple arbitrary waveform generators (AWG) or direct digital synthesizers (DDS), wherein each AWG / DDS independently controls the channel of the AOM for the corresponding addressing beam. Therefore, each Raman beam in the corresponding channel may include a different phase, amplitude, and / or frequency. In some examples, the polarization of the Raman beam may also be modulated or controlled. Individually controlled addressing Raman beams and counter-propagating global Raman beams may tune the state of trapped ions by relying on the Raman beat between the individually controlled Raman beams and the global Raman beam. Synchronous control of Raman beams (single tone or multi-tone) allows the state of trapped ions to be controlled individually or simultaneously by a multi-channel AOM. In some embodiments, synchronous control of the addressing beams may reduce the delay in changing the state of the trapped ions and compensate for any energy shift caused by the illumination of the global beam.

[0035] In other embodiments, the optical setup associated with a multi-channel AOM can direct individually controlled Raman beams toward trapped ions despite different deflection / diffraction angles upon exiting the AOM.

[0036] In some examples, individually controlled Raman beams of a multi-channel AOM can advance the phase of a trapped ion to correct or mitigate errors caused by energy offsets during quantum gate operations.

[0037] The following, combined Figure 1A to Figure 8 Various aspects associated with the solution to the above-mentioned problem are explained in more detail.

[0038] Figure 1A A diagram 100 is shown illustrating a vacuum chamber with a plurality of atomic ions 106 trapped in a linear crystal 110 using a linear RF Paul trap (the linear crystal 100 may be located within the vacuum chamber which is not shown). Figure 1A In the illustrated example, the vacuum chamber in the quantum system includes a plurality of (e.g., N>1, where N is a number greater than or equal to 100, and in some embodiments, N=32) atomic ytterbium ions (e.g., 171 Yb + ions). The number of trapped atomic ions can be settable, and more or fewer atomic ions can be trapped. 171 Yb +The atoms are illuminated by laser (light) radiation resonating in the medium, and the fluorescence of the atomic ions is imaged on a camera. In this example, the atomic ions are separated from each other by about 5 micrometers (μm), as shown by the fluorescence. The separation of the atomic ions is determined by the balance between external binding forces and Coulomb repulsion.

[0039] Strong fluorescence of individual trapped atomic ions depends on efficient recycling of photons, so the atomic structure of the ions must have strong closed optical transitions to allow laser cooling of motion, qubit state initialization, and efficient qubit readout. This may rule out many atomic ion species, except for simple atomic ions with a single outer electron, such as alkaline earth (Be + Mg + , Ca + , Sr + , Ba + ) and certain transition metals (Zn + , Hg + 、Cd + , and Yb + ). In these atomic ions, a qubit can be represented by two stable electronic energy levels, often characterized by an effective spin with two states |↑> and |↓>, or equivalently |1> and |0>. Figure 1B and Figure 1C Atomic ions are shown separately 171 Yb + Simplified energy level diagrams 120 and 150 of FIG. 1 , where the qubit energy levels |↑> and |↓> 130 are represented by stable hyperfine energy levels in the ground state electronic state and the frequency spacing is ω0 / 2π = 12.642812 GHz. 171 Yb + The excited electronic states |e> and |e`>140 in are themselves split by a small hyperfine coupling and are separated from the ground state by an optical interval with an energy corresponding to a light wavelength of 369.53 nm.

[0040] Laser radiation tuned to just below the resonance in these optical transitions allows Doppler laser cooling to pin atomic ions near the bottom of the trap. Other more sophisticated forms of laser cooling can keep atomic ions nearly immobile in the trap.

[0041] When with and When a two-color laser or light beam (e.g., a beam with two tones produced by light modulation producing sidebands) that resonates with both transitions is applied to the atom, it rapidly falls into the state |↓> and no longer interacts with the light field, allowing the qubit to be initialized with essentially 100% fidelity (e.g., see Figure 1B ).

[0042] When applied with When a single laser or beam is in resonance with the transition, the closed loop optical transition causes the ions in the |↑> state to fluoresce strongly, while the ions in the |↓> state remain dark because the laser frequency is far from its resonance (see, for example, Figure 1C ). Collecting even a small fraction of this fluorescence can detect the atom’s qubit state with near-perfect efficiency or accuracy. Other atomic species can have similar initialization / detection schemes.

[0043] exist Figure 1B and 1C In the diagram, all allowed transitions from excited electronic states |e> and |e'>140 are illustrated as downward wavy arrows. On the other hand, the applied laser radiation (shown as upward straight arrows) drives these transitions for initialization to the state |↓>, as Figure 1B As shown, and for fluorescence detection of the qubit state (|↑>=fluorescence, |↓>=no fluorescence), as Figure 1C shown.

[0044] For coherent transitions between qubit energy levels, there can be single-qubit rotation operations and entangled multi-qubit operations. Single-qubit rotation operations can also be called single-qubit operations or simply qubit flips.

[0045] Regarding the single-qubit rotation operation, Figure 1B and Figure 1C The qubit energy levels |↑> and |↓>130 in can be directly coupled with the external control field, leading to single-qubit rotation operations. ik·x-iωt-iψ The operating wave (resonant) field described by , where k is the wave vector, ω is the field frequency, ψ is the phase, and the result at resonance (ω = ω0) is a rotation operation on the qubit at position x (assuming the rotation wave approximation and that the phase ψ is constant during the operation), as shown in the following equations (1) and (2):

[0046]

[0047]

[0048] where θ = Ωt, φ = k·x-ψ. Here, Ω = μE0 / h is the Rabi frequency, which parameterizes the field-qubit coupling, assuming an effective dipole transition with moment μ. For a coupled dual-field optical Raman field A and B via an intermediate virtual energy level, the effective Rabi frequency is related to Ω A Ω B The effective frequency of the field becomes ω A -ω B The wave vector k is the difference between the two fields δk = k A -k Bis given, and the phase becomes the phase difference δφ=δk·x-(ψ A -ψ B ). In practice, the two Raman fields must bridge the qubit frequency splitting ω0. This can be achieved with discrete modulation elements or using a mode-locked frequency comb laser. An optical frequency comb is a laser source whose spectrum has a series of discrete, equally spaced frequency lines. The comb effect can be generated by a variety of mechanisms, including periodic modulation (e.g., amplitude and / or phase) of a continuous wave laser, four-wave mixing in a nonlinear medium, or stabilization of a pulse train generated by a mode-locked laser (e.g., the mode-locked frequency comb laser described above).

[0049] For 2 consecutive rotations on the qubit with a time interval T, the accumulated qubit phase is ψ + ωT. If the control field is a single field coupling in the optical domain, this may require controlling both the optical frequency and phase in extended operations (e.g., longer or more correlated operations). However, for Raman coupling of two optical fields between the qubits, the accumulated qubit phase is ψ A -ψ B +(ω A -ω B )T, the frequency difference needs to be controlled A -ω B and the phase difference ψ A -ψ B .

[0050] For entangled multi-qubit operations, the motion of many trapped ions is coupled via Coulomb interactions, like an array of pendulums connected by springs. The natural way to implement entangled quantum logic gates between atomic ions in a crystal is to use motion as an intermediary, such as Figure 2A , which shows a diagram 200 illustrating an example of the geometry of a Raman beam, wherein the application of the beam produces motion in a qubit. In diagram 200, there are individual beams 210 and a global beam 220 directed to a linear crystal 110 having atomic ion qubits. Beams in the same direction may be referred to as co-propagating beams, while beams in different or opposite directions may be referred to as non-co-propagating or counter-propagating beams, respectively. Individual beams 210 (co-propagating) are focused or individually addressed beams, while global beams 220 (counter-propagating relative to individual beams 210, as shown) may be non-focused global beams. As used herein, the terms "laser beam", "beam", "beam", "laser", "light field", and "field" may be used interchangeably.

[0051] Using motion as an intermediary, quantum logic gates can be accomplished by applying a light or microwave dipole force to the atomic ions that is dependent on the qubit state. There are many protocols for using such externally applied forces that are dependent on the qubit state to create controlled NOT gates and other related multi-qubit entanglement operations. While phase correlations are similar in many similar classes of gates, the most common one between two trapped ion qubits is Gate operation (also called MS, Ising, or XX gate operation).

[0052] Still reference Figure 2A , Figure 200 shows the geometry of Raman beams for an example of a 2-qubit gate between select ions as shown. The counter-propagating beam (paired beam) 210 and the beam propagating in the opposite direction 220 overlap on the two trapped ions, and the Raman transitions coupled as collective motion modes allow entanglement operations. For single-qubit rotations, individual ions are addressed, and for the counter-propagating geometry this may not be necessary. For single-qubit gates, this operation involves spin flips, also called carrier transitions or resonant qubit transitions. For two-qubit gates, this operation tends to drive motional sidebands, and these frequencies deviate somewhat from the frequencies used in the single-qubit transitions.

[0053] Consider the frequency ω m Collects the coupling of a single mode of ion motion. Typically, The gate operation requires two non-co-propagating or counter-propagating laser beams (A and B) with wave vector k A and k B , which together drive the transitions of the upper and lower sidebands. The beam along direction A has a single frequency component ω A , whose optical phase is ψ A , while the beam along direction B has 2 frequencies Its optical phase is ψ B , so the resulting 2 beats between A and B are close to the upper (+) and lower (-) sideband transitions. There are 2 spectrum configurations that can produce these two-color beats on beam B about the frequency of beam A, as shown in equations (3) and (4) below:

[0054] “Phase sensitive”…(3)

[0055] “Phase insensitivity”…(4)

[0056] That is, one possible configuration of two-color beats on beam B is phase-sensitive (Equation (3)), while another possible configuration is phase-insensitive (Equation (4)).

[0057] As mentioned above, equations (3) and (4) assume that for A minus sign should be added to the right side of equations (3) and (4).

[0058] An important aspect is that the phase-insensitive configuration has upper and lower sideband beats of opposite signs (ω0>>ω m ±δ), so the optical phase accumulated from the interaction involving the two beats will be cancelled. The two-qubit evolution under the XX gate is shown in the following equation (5):

[0059] |00>→|00>-i|11>e -iχ (5)

[0060] |11>→|11>-i|00>

[0061] |01>→|01>-i|10>

[0062] |10>→|10>-i|00〉e iχ

[0063] In the case of phase sensitivity, the effective phase of the XX gate is χ = (ψ A -ψ B ), for the phase-insensitive case, χ=0.

[0064] For the phase sensitive case, the actual phase accumulated by the gate depends on the optical phase of the beams, since the effective optical path length difference between the two Raman beams will vary due to mechanical and thermal fluctuations in the beam paths, so the actual phase will drift slowly over time. Even in this case, by fully controlling the phase, frequency, and / or amplitude of the Raman beams (e.g., by using a multi-channel AOM), it is possible to add enough single-qubit rotations before and after the two-qubit gate so that the combined operation functions as a two-qubit gate with a well-defined phase shift that determines the properties of the gate, as long as the optical path length remains stable for the duration of the combined manipulation. This is another phase correction method that can be implemented using the techniques and systems described in this disclosure.

[0065] In view of the above, and because synchronization, stabilization, and control of qubit phases are critical to the performance of extended quantum operations, the present disclosure provides various techniques that can be used to control trapped ion qubits (e.g., phase, amplitude, frequency, polarization, etc.). Accordingly, various techniques for manipulating optical fields (e.g., laser beams) are described below to enable phase control of qubit operations for extended qubit operations, where drift of the optical phase can lead to decoherence. The polarization of the Raman beam required to drive the qubit transition depends on the atomic structure of the qubit energy levels and their coupling to excited states. As an example, the present disclosure considers Figure 2B The energy level diagram 230 is shown in 171 Yb +A system in which coherent stimulated Raman transitions couple two qubit states labeled |0> and |1> separated by a frequency of ω q , and for these two Raman beams, a 355nm laser with σ + / σ + or σ_ / σ_ polarized laser field (for example, any Raman process is driven by a laser field with polarization σ + or σ_ of 2 beams). However, it should be understood that, except 171 Yb + In addition to systems, systems with possibly different energy levels and transition selection rules can also be used in combination with the features described herein.

[0066] As discussed above, it is important to control how a light field or beam (eg, produced by a laser or other light source) is directed, including, for example, controlling its geometry, polarization, and / or frequency.

[0067] Now go to Figure 3 , is an example of a system 300 supporting multi-qubit control using an acousto-optic modulator (AOM) 310. The system 300 may be a combination of the following Figure 6 , 7A 7B and 7C. The system 300 includes a linear crystal 110 having trapped ions 306a-d (corresponding to Figure 1A The trapped ions 306a-d may be illuminated by the global beam 220 from a first direction and illuminated by the individually addressed beams 210a-d from a second direction different from the first direction. In one embodiment, the second direction of the global beam 220 may be substantially opposite or exactly opposite to the first direction of the individually addressed beams 210a-d (see, for example, Figure 2A In another embodiment, the second direction of the global light beam 220 may deviate from the first direction of the individual addressing light beams 210a-d by approximately or exactly 90 degrees (or 270 degrees), as in Figure 3 20 and 210, as shown by the optional directions of the global beam 220 shown in dashed lines. In other words, the global beam 220 and the individually addressed beams 210a-d are directed at the trapped ions 106a-d from different directions in the same plane, or in a perpendicular plane. It should be understood that combinations of directions are also possible, where for some trapped ions, the directions of the beams are approximately opposite or opposite, while for other trapped ions, the directions of the beams are approximately or exactly 90 degrees (or 270 degrees) offset from each other. The term "approximately" as used herein can refer to a deviation from a nominal value or a characteristic value, where the deviation is within 0.5%, 1%, 2%, 3%, 4%, 5%, or 10% of the nominal value.

[0068] Despite Figure 3 4 trapped ions 306a-d are shown by way of illustration, but the linear crystal 100 may have 1, 2, 5, 6, 10, 16, 20, 32, 50, 64, 128 or more trapped ions, and any subset of these trapped ions may be used in implementing various quantum gates. The AOM 310 may be a multi-channel Bragg cell having piezoelectric transducers 312a-d (e.g., arranged in parallel) that locally apply acoustic waves to the AOM 310. The AOM 310 may include a different channel for each trapped ion 106. The controller 320 (which may be a combination of the following) may be provided with waveform generators 322a-d. Fig. 7A and 7B The piezoelectric transducers 312a-d are controlled by the optical controller 720 as described above. The waveform generators 322a-d may be arbitrary waveform generators (AWGs), and / or direct digital synthesizers, or other types of signal generating devices. During operation, in some embodiments, the global beam 220 may illuminate the trapped ions 306a-d from a first direction. The global beam 220 may be a Raman beam from one or more Raman lasers. The global beam 220 may be focused onto the trapped ions 306a-d using an optical device (e.g., a lens, a reflector, etc., not shown) (e.g., see FIG. 2 ). Figure 4 ). The global beam 220 can have a single frequency, phase, and amplitude. Individual addressing beams 210a-d can be provided to illuminate some of the trapped ions 306a-d respectively from a second direction. The trapped ions 306 that are illuminated depend on the quantum gate implemented in the current stage of the sequence as part of the quantum operation or algorithm. For example, the individual addressing beam 210a can illuminate the trapped ion 306a. The individual addressing beam 210b can illuminate the trapped ion 306b. The individual addressing beam 210c can illuminate the trapped ion 306c. The individual addressing beam 210d can illuminate the trapped ion 306d. In some examples, some trapped ions (not shown) are not illuminated by any individual addressing beams. In other embodiments, it may be advantageous to illuminate all of the trapped ions 306a-d to correct for any energy shift (discussed below) caused by the illumination of the global beam 220.

[0069] Still reference Figure 3In some embodiments, the frequency, amplitude, and / or phase of each individual addressing beam 210a-d can be modulated by the AOM 310. For example, the waveform generator 322a can cause the transducer 312a to generate a first acoustic wave having a first predetermined mass. The first acoustic wave generated by the transducer 312a can cause the individual addressing beam 210a to have a first frequency, a first phase, and / or a first amplitude. The difference between the first frequency and the frequency of the global beam 220 can generate a first beat for controlling the state of the trapped ion 306a. Using this method, the first frequency, the first phase, and / or the first amplitude can be dynamically changed over time. The waveform generator 322b can cause the transducer 312b to generate a second acoustic wave having a second predetermined mass. The second acoustic wave generated by the transducer 312b can cause the individual addressing beam 210b to have a second frequency, a second phase, and / or a second amplitude. The difference between the second frequency and the frequency of the global beam 220 can generate a second beat for controlling the state of the trapped ion 306b. Using this method, the second frequency, the second phase, and / or the second amplitude can be dynamically changed over time.

[0070] Still reference Figure 3 In some examples, waveform generator 322c can cause transducer 312c to generate a third acoustic wave having a third predetermined mass. The third acoustic wave generated by transducer 312c can cause individual addressing beam 210c to have a third frequency, a third phase, and / or a third amplitude. The difference between the third frequency and the frequency of global beam 220 can generate a third beat for controlling the state of trapped ion 306c. Using this method, the third frequency, the third phase, and / or the third amplitude can be dynamically changed over time. Waveform generator 322d can cause transducer 312d to generate a fourth acoustic wave having a fourth predetermined mass. The fourth acoustic wave generated by transducer 312d can cause individual addressing beam 210d to have a fourth frequency, a fourth phase, and / or a fourth amplitude. The difference between the fourth frequency and the frequency of global beam 220 can generate a fourth beat for controlling the state of trapped ion 306d. Using this method, the fourth frequency, the fourth phase, and / or the fourth amplitude can be dynamically changed over time. Since the individual addressing beams 210a-d can be individually modulated by the controller 320 (via waveform generators 322a-d) and the AOM 310 (via transducers 312a-d), the individual addressing beams 210a-d and the global beam 220 can collectively generate up to four beats to independently control the states of the trapped ions 306a-d. It should be understood that the global beam 220 can also be controlled by the controller 320 or a different controller. Although four trapped ions 306 have been described in this example, the number of trapped ions and / or which trapped ions are provided with individual modulation of the addressing beam 210 can vary over time based on the stacking of quantum gates (e.g., multi-level quantum gates) implemented as part of a sequence in a quantum operation.

[0071] Now go to Figure 4 The example of the multi-tone Raman beam alignment system 400 can be used to focus a diffracted Raman beam onto a trapped ion for implementation of certain quantum gate operations, such as the above combination Figure 3 For example, the alignment system 400 (which may be part of the computer device 600 and / or the QIP system 700) may include a multi-channel AOM 402 (which may be Figure 3 ), for simplicity, a single channel is illustrated (other channels may be located in Figure 4 For the channel shown, the alignment system 400 may include a waveform generator 404, a transducer 406, and a lens assembly 408. Similar structures may be used for other channels in the multi-channel AOM 402.

[0072] During operation, in some embodiments, the transducer 406 (under the control of the waveform generator 404) can generate acoustic waves having frequencies f1 and f1'. As a result, an incident Raman beam 410 (e.g., one of the individual addressing beams 210) can be generated and provided to the AOM 402, and can be diffracted into an output beam 412 (undeflected), an output beam 414 (having a frequency f1), and an output beam 416 (having a frequency f1'), wherein the output beams 414, 416 have different diffraction angles. The output beams 414, 416 can pass through the lens assembly 408 and can be redirected into reflected beams 420, 422, respectively. The reflected beams 420, 422 can be refocused onto the trapped ions 430 by the lens assembly 408. Although the lens assembly 408 is shown as a single optical element, the present disclosure is not limited thereto, and the lens assembly 408 can include multiple optical elements, such as including different types of lenses.

[0073] Now go to Figure 5 An example of a gate sequence 500 for a three-qubit system includes gates based on trapped ions 502, 504, 506 (which may correspond to Figure 1A and 3 Single qubit gates 510 (Q1), 512 (Q2), 514 (Q3), 528 (Q5), 538 (Q7), 540 (Q8), 542 (Q9), and double qubit gates 522 (Q4), 532 (Q6) based on trapped ions in a linear crystal 110 in FIG. 1 . In some embodiments, executing quantum gates of qubits based on trapped ions 502, 504, 506 may result in a shift in the energy splitting of the qubits. This causes a phase advance of the qubit based on the energy shift and the duration of the gate, and is a cause of errors in quantum operations or algorithms. To eliminate this error caused by energy shifts, for example, a beam with individually addressable beams may be used. Figure 3 The multi-channel AOM system of FIG. 5 advances the phase of the Raman beat of each trapped ion 502, 504, 506. The timing of such phase advances can occur at positions 516, 518, 520, 524, 526, 530, 534, and 536. That is, after the first stage of the sequence including a set of quantum gates (Q1, Q2, Q3), phase advances p11, p21, and p31 can be performed on each gate, respectively. Similarly, after the second stage including the dual-qubit gate Q4, phase advances p12 and p22 can be performed with respect to the trapped ions 502 and 504. After the third stage including the single-qubit gate Q5, phase advance p23 can be performed with respect to the trapped ion 504. After the fourth stage of the sequence including the dual-qubit gate Q6, phase advances p24 and p32 can be performed with respect to the trapped ions 504 and 506. The fifth stage in the sequence includes a group of quantum gates Q7, Q8, and Q9, and a subsequent phase advance may also be performed (although not shown in this example). This example is provided by way of illustration, and a similar approach may be applied when the number of qubits considered is greater or less than 3 and when the number of stages in the sequence is less or greater than 5.

[0074] Still reference Figure 5 , qubit energy shifts may originate from the illumination of the trapped ions by the global beam 220. Since energy from the global beam 220 is transferred to the trapped ions (e.g., the trapped ions 502, 504, and 506) during illumination, there may be unintended residual manipulation of the trapped ions. By separately controlling the beam characteristics of the individual addressing beams 210 provided to the trapped ions 502, 504, and 506 by, for example, the AOM 310, the AOM 310 may be used to continuously compensate for the energy shift caused by the global beam 220. For example, if the global beam 220 induces an energy shift in the trapped ion 502, the corresponding individually addressable beams 210 may be used to correct or mitigate the energy shift and thereby reduce the likelihood of systematic errors. One way to do this is to perform phase advance as described above.

[0075] Reference now Figure 6 , which shows an example computer device 600 based on various aspects of the present disclosure. For example, computer device 600 can represent a single computing device, multiple computing devices, or a distributed computing system. Computer device 600 can be configured as a quantum computer (e.g., a quantum information processing (QIP) system), a classical computer, or a combination of quantum and classical computing functions. For example, computer device 600 can be used to process information using quantum algorithms based on trapped ion technology, and thereby can implement methods for independent control of Raman beams in multi-channel AOMs, as described in the present invention, applied to quantum logic gates, and related to generalized interactions between qubits. In Fig. 7Aand Figure 7B In the illustrated example, a general example of a computer device 600 as a QIP system capable of implementing the various beam controls described herein is shown.

[0076] In one example, the computer device 600 may include a processor 610 for implementing processing functions associated with one or more features described herein. The processor 610 may include one or more groups of processors or a multi-core processor. In addition, the processor 610 may be implemented as an integrated processing system and / or a distributed processing system. The processor 610 may include a central processing unit (CPU), a quantum processing unit (QPU), a graphics processing unit (GPU), or a combination of these types of processors. When quantum operations are supported, the processor 610 may include at least trapped ions to implement quantum operations. On the one hand, the processor 610 may refer to a general-purpose processor of the computer device 600, which may also include additional processors 610 to perform more specific functions, such as functions for individual addressing beam control.

[0077] In an example, the computer device 600 may include a memory 620 for storing instructions executable by the processor 610 for implementing the functions described herein. In one embodiment, for example, the memory 620 may correspond to a computer-readable storage medium that stores codes or instructions for performing one or more functions or operations described herein. In an example, the memory 620 may include a processor 610 for executing the following instructions. Figure 8 Instructions for various aspects of the described method 800. As with the processor 610, the memory 620 may refer to general memory of the computer device 600, which may also include additional memory 620 to store instructions and / or data for more specific functions, such as instructions and / or data for individual bundle control.

[0078] In addition, the computer device 600 may include a communication component 630 for establishing and maintaining communications with one or more parties using the hardware, software, and services described herein. The communication component 630 enables communication between components on the computer device 600 and between the computer device 600 and external devices (such as devices located on a communication network and / or devices serially or locally connected to the computer device 600). For example, the communication component 630 may include one or more buses, and may further include a transmit chain component and a receive chain component associated with a transmitter and a receiver, respectively, which are operable to interface with external devices.

[0079] In addition, the computer device 600 may include a data store 640, which may be any suitable combination of hardware and / or software for mass storage of information, databases, and programs used in conjunction with the implementations described herein. For example, the data store 640 may be a data repository for an operating system 660 (e.g., a classical OS or a quantum OS). In one embodiment, the data store 640 may include a memory 620.

[0080] The computer device 600 may also include a user interface component 650, which is operable to receive input from a user of the computer device 600, and is also operable to generate output to be presented to the user or (directly or indirectly) provided to different systems. The user interface component 650 may include one or more input devices, including but not limited to a keyboard, a numeric keypad, a mouse, a touch-sensitive display, a digitizer, a navigation key, a function key, a microphone, a speech recognition component, any other mechanism that can receive input from the user, or any combination thereof. In addition, the user interface component 650 may include one or more output devices, including but not limited to a display, a speaker, a tactile feedback mechanism, a printer, any other mechanism that can present output to the user, or any combination thereof.

[0081] In one embodiment, the user interface component 650 may send and / or receive messages corresponding to the operation of the operating system 660. In addition, the processor 610 may execute the operating system 660, and / or applications, or programs, and the memory 620 or the data storage 640 may store them.

[0082] When the computer device 600 is implemented as part of a cloud-based infrastructure solution, the user interface component 650 may be used to allow a user of the cloud-based infrastructure solution to interact with the computer device 600 remotely.

[0083] Fig. 7A is a block diagram illustrating an example of a QIP system 700 based on various aspects of the present disclosure. The QIP system 700 may also be referred to as a quantum computing system, a computer device, etc. In one aspect, the QIP system 700 may correspond to Figure 6 The computer device 600 in the quantum computer implementation is part of the invention.

[0084] QIP system 700 may include a chamber 750 (eg, Figure 1A A source 760 of atomic species (e.g., a stream of neutral atoms) is provided in a vacuum chamber in the chamber 750, the chamber 750 having a trapping light controller 720 (e.g., see Figure 7B) ion trap 770 of atomic species that are ionized (e.g., photoionized). The light source 730 in the optical controller 720 may include one or more laser sources (e.g., a source of light beams or laser beams) that may be used for ionization of atomic species, control of atomic ions, fluorescence of atomic ions that can be monitored and tracked by an image processing algorithm running in an imaging system 740 in the optical controller 720, and / or performing optical control functions described in the present disclosure. In one aspect, the light source 730 may be implemented separately from the optical controller 720.

[0085] The imaging system 740 may include a high-resolution imager (e.g., a CCD camera) for monitoring the atomic ions as they are provided to the ion trap or after the atomic ions have been provided to the ion trap 770. In one aspect, the imaging system 640 may be implemented separately from the optical controller 720, however, utilizing image processing algorithms to detect, identify, or label the atomic ions using fluorescence may require coordination with the optical controller 720.

[0086] The QIP system 700 may also include an algorithm component 710 that may operate with other portions of the QIP system 700 (not shown) to perform quantum algorithms or quantum operations including stacks or combinatorial sequences of single-qubit operations and / or multi-qubit operations (e.g., double-qubit operations), and extended quantum computations. In this way, the algorithm component 710 may provide instructions to various components of the QIP system 700 (e.g., to the optical controller 720) to enable implementation of the quantum algorithms or quantum operations, and thereby implement the various individually addressed beam control techniques described herein.

[0087] Figure 7BAt least a portion of the optical controller 720 is shown. In this example, the optical controller 720 may include a light source 730 and an imaging system 740. As shown by the dashed lines, one or both of the light source 730 and the imaging system 740 may be optionally implemented separately from the optical controller 720 but in communication with the optical controller 720. The imaging system 740 includes a CCD 741 (or a similar imager or camera) and an image processing algorithm component 742. The light source 730 includes an AWG (or DDS) 732a-d and a laser source 734a-d, which may be used for one or more functions of the above-mentioned individually addressed beam control. The light source 730 may also include a global modulator 736 and a global laser source 738 for emitting and controlling the global Raman beam 220. In addition, the optical controller 720 may include a multi-channel AOM controller 737 configured to control the operation of a multi-channel AOM 738, which may correspond to the multi-channel AOM 310 described above. As described above, a multi-channel AOM 738 may be implemented using a single AOM device having multiple channels, multiple AOM devices having a single channel, or multiple AOM devices having multiple and / or single channels. The multi-channel AOM controller 737 may also be configured to monitor or track the phase shift of individual trapped ions to correct or mitigate their effects by using, for example, the phase advance technique described above. Although not shown, Figure 4 The alignment system 400 in can also be implemented as a component of the optical controller 720.

[0088] refer to Figure 8 , is a method 800 of controlling quantum states of ions in an ion chain for quantum manipulation. In one aspect, the method 800 can be performed in a computer system such as the computer device 600 described above, where, for example, the processor 610, the memory 620, the data storage 640, and / or the operating system 660 can be used to perform the functions of the method 800. Similarly, the functions of the method 800 can be performed by one or more components of a QIP system such as the QIP system 700 and its components (e.g., the optical controller 720 and its subcomponents).

[0089] At block 802 , method 800 may include providing a global beam (eg, global beam 220 ) to ions in an ion chain (eg, linear crystal 110 ) from a first direction.

[0090] In block 804, method 800 may include providing a respective addressing beam (e.g., addressing beam 210) to each ion in the subset of ions in the ion chain from a second direction different from the first direction. In one example, the second direction is opposite to the first direction. In another example, the second direction is 90 degrees off from the first direction.

[0091] At block 806, method 800 may include dynamically controlling each provided addressing beam using a corresponding channel in a multi-channel AOM (e.g., AOM 310) to implement a quantum gate sequence of quantum operations (e.g., Figure 5 One or more quantum gates in a sequence of quantum gates in .

[0092] In one aspect of method 800, the method further includes monitoring (e.g., via an optical controller 720 and / or a multi-channel AOM controller 737) a cumulative phase shift of each of a plurality of ions in an ion chain, wherein dynamically controlling each provided addressing beam includes independently modulating each provided addressing beam to correct the cumulative phase shift in the corresponding ions.

[0093] In one aspect of method 800, dynamically controlling each provided addressing beam includes independently modulating each provided addressing beam to control one or more beam characteristics of the corresponding addressing beam. The one or more beam characteristics include one or more of frequency, phase, and amplitude. In some cases, polarization may also be a characteristic of the beam, which may require some form of control. In addition, independently modulating each provided addressing beam includes independently modulating an RF signal applied to a corresponding channel in the AOM to modify the beam characteristics of the corresponding addressing beam.

[0094] In one aspect of method 800, the sequence of quantum gates of the quantum operation includes one or more single-qubit gates, one or more two-qubit gates, or a combination thereof (see, e.g., Figure 5 ). For any one of the one or more single-qubit gates, dynamically controlling the corresponding addressing beam to have a single frequency or tone to produce a spin flip. For any one of the one or more two-qubit gates, dynamically controlling the corresponding addressing beam to have two frequencies or tones to drive a motion sideband.

[0095] In one aspect of method 800, a corresponding addressing beam is then provided to each ion in a different subset of ions in the ion chain from a second direction; and each addressing beam provided to the different subset of ions in the ion chain is dynamically controlled by using a corresponding channel in a multi-channel AOM to implement one or more different quantum gates in a quantum gate sequence for quantum operations using the ion chain.

[0096] In one aspect of the method 800, the global beam provided from the first direction and each addressing beam provided from the second direction operate as counter-propagating Raman beams.

[0097] The above description of the present disclosure is provided to enable those skilled in the art to make or use the present disclosure. Various modifications to the present disclosure will be apparent to those skilled in the art, and the common principles defined herein can be applied to other variations without departing from the spirit or scope of the present invention. In addition, although the elements of the various aspects described may be described or claimed in singular form, the plural may also be considered unless expressly stated to be limited to the singular form. In addition, unless otherwise stated, all or a portion of any aspect may be used together with all or a portion of any other aspect. Therefore, the present disclosure is not limited to the examples and designs described, but should be given the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method of controlling the quantum state of ions in an ion chain for quantum manipulation, comprising: providing a global beam from a first direction to ions in the ion chain; providing a respective addressing beam to each ion in a subset of ions in the ion chain from a second direction different from the first direction; Dynamically controlling each of the provided addressing beams using a corresponding channel in a multi-channel acousto-optic modulator (AOM) to implement one or more quantum gates in a quantum gate sequence of the quantum operation using the subset of ions in the ion chain; optically monitoring a cumulative phase shift of each ion in the ion chain; and The accumulated phase shift in the corresponding ion is corrected by applying a phase advance to the Raman beat of the corresponding addressing beam simultaneously after each output of each stage of the gate in the stage sequence of the quantum operated gate. The method of claim 1 , wherein the first direction and the second direction are in perpendicular planes. 3 . The method of claim 1 , wherein for a first portion of ions in the ion chain, the second direction is opposite to the first direction, and for a second portion of ions in the ion chain, the second direction deviates from the first direction by 90 degrees.

4. The method of claim 1 , wherein dynamically controlling each of the provided addressing beams comprises: Each of the addressing beams provided is independently modulated to correct for the accumulated phase shift of the corresponding ions.

5. The method of claim 1 , wherein dynamically controlling each of the addressing beams provided to implement the one or more quantum gates comprises: A single qubit rotation is achieved before a two-qubit gate, and another single qubit rotation is achieved after the two-qubit gate, such that the combination of the two qubit rotations and the two-qubit gate is insensitive to the relative optical phases of the global beam driving the Raman transition and the corresponding addressing beam.

6. The method of claim 1 , wherein dynamically controlling each of the addressing beams provided comprises: Each of the provided addressing beams is independently modulated to control one or more beam characteristics of the corresponding addressing beam.

7. The method of claim 6, wherein the one or more beam characteristics include one or more of frequency, phase, amplitude, or polarization.

8. The method of claim 6, wherein independently modulating each of the provided addressing beams comprises: Radio frequency (RF) signals applied to corresponding channels in the AOM are independently modulated to modify beam characteristics of the corresponding addressing beams.

9. The method of claim 1, wherein the quantum gate sequence of the quantum operation comprises one or more single-qubit gates, one or more two-qubit gates, or a combination thereof.

10. The method of claim 9, wherein for any of the one or more single-qubit gates, the corresponding addressing light beam is dynamically controlled to have a single frequency or tone to produce a spin flip.

11. The method of claim 9, wherein for any one of the one or more two-qubit gates, the corresponding addressing beam is dynamically controlled to have 2 frequencies or tones to drive the motion sidebands.

12. The method according to claim 1, further comprising: then providing a respective addressing beam from the second direction to each ion in a different subset of ions in the ion chain; and Each of the addressing beams provided to the different subsets of ions in the ion chain is dynamically controlled using a corresponding channel in the multi-channel AOM to implement one or more different quantum gates in the quantum gate sequence of the quantum operation using the different subsets of ions in the ion chain. 13 . The method according to claim 12 , wherein the second direction is opposite to the first direction, or the second direction deviates from the first direction by 90 degrees.

14. The method of claim 1, wherein the global beam provided from the first direction and each of the addressing beams provided from the second direction operate as counter-propagating Raman beams.

15. A quantum information processing (QIP) system for controlling the quantum state of ions in an ion chain for quantum operations, the QIP system comprising: an ion trap configured to implement the ion chain; a first light source configured to provide a global light beam from a first direction to ions in the ion chain; a set of second light sources configured to provide a respective addressing light beam to each ion in a subset of ions in the ion chain from a second direction different from the first direction; Multi-channel acousto-optic modulator AOM; and An optical controller configured to dynamically control the set of second light sources to control each of the addressing beams provided by the corresponding channel in the multi-channel AOM to implement one or more quantum gates of the quantum gate sequence of the quantum operation using a subset of ions in the ion chain, wherein the optical controller is further configured to optically monitor the accumulated phase shift of each ion in the ion chain; and correct the accumulated phase shift in the corresponding ion by simultaneously applying a phase advance to the Raman beat of the corresponding addressing beam after each output of each stage of the gate in the stage sequence of gates of the quantum operation.

16. The QIP system of claim 15, wherein the first direction and the second direction are in vertical planes.

17. The QIP system of claim 15, wherein for a first portion of ions in the ion chain, the second direction is opposite to the first direction, and for a second portion of ions in the ion chain, the second direction deviates from the first direction by 90 degrees.

18. The QIP system of claim 15, further comprising: An algorithm component is configured to provide instructions associated with the quantum gate sequence of the quantum operation to the optical controller to dynamically control the set of second light sources to implement the one or more quantum gates in the quantum gate sequence.

19. The QIP system of claim 15, wherein: The optical controller includes one or more waveform generators and is configured to dynamically control each of the provided addressing beams to correct the accumulated phase shift of the corresponding ions by independently modulating each of the provided addressing beams using the one or more waveform generators.

20. The QIP system of claim 15, wherein the optical controller configured to dynamically control the set of second light sources to control each of the provided addressing beams to implement the one or more quantum gates is further configured to: implement a single qubit rotation before a two-qubit gate, and implement another single qubit rotation after the two-qubit gate, such that the combination of the two qubit rotations and the two-qubit gate is insensitive to the relative optical phase of the global beam driving the Raman transition and the corresponding addressing beam.

21. The QIP system of claim 15, wherein the optical controller comprises one or more waveform generators and is configured to dynamically control each of the provided addressing beams by independently modulating each of the provided addressing beams using the one or more waveform generators to control one or more beam characteristics of the corresponding addressing beams.

22. The QIP system of claim 21, wherein the one or more beam characteristics include one or more of frequency, phase, amplitude, or polarization.

23. The QIP system of claim 21, wherein independently modulating each of the provided addressing beams using the one or more waveform generators comprises: Radio frequency (RF) signals applied to corresponding channels in the AOM are independently modulated to modify the beam characteristics of the corresponding addressing beams.

24. The QIP system of claim 15, wherein the quantum gate sequence of the quantum operation comprises one or more single-qubit gates, one or more two-qubit gates, or a combination thereof.

25. The QIP system of claim 24, wherein the optical controller is configured to dynamically control the corresponding addressing beam for any of the one or more single-qubit gates to have a single frequency or tone to produce a spin flip.

26. The QIP system of claim 24, wherein the optical controller is configured to dynamically control the corresponding addressing beam for any of the one or more two-qubit gates to have 2 frequencies or tones to drive the moving sidebands.

27. The QIP system of claim 15, wherein: The set of second light sources is configured to subsequently provide a respective addressing light beam to each ion in a different subset of ions in the ion chain from the second direction, and The optical controller is configured to dynamically control each of the addressing beams provided to the different subsets of ions in the ion chain by using a corresponding channel in the multi-channel AOM to implement one or more different quantum gates in the quantum gate sequence of the quantum operation using the different subsets of ions in the ion chain.

28. The QIP system of claim 27, wherein the second direction is opposite to the first direction, or the second direction is offset from the first direction by 90 degrees.

29. The QIP system of claim 15, wherein the global beam provided from the first direction and each of the addressing beams provided from the second direction operate as counter-propagating Raman beams.

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