5 results about "Linear element" patented technology

Various examples are provided related to overcurrent protection for composite power semiconductor switches comprising a high voltage power switch in series with a low voltage non-linear element. In one example, a system includes a blocking diode connected to a sensing node of a composite switching device; a resistor connected in series with the blocking diode and to a desaturation detection input of a gate driver circuit; and a blanking capacitor connected between the desaturation detection input and a common voltage reference of the gate driver circuit. The gate driver circuit can detect a short circuit condition based upon a sensed voltage at the desaturation detection input. In another example, a method includes sensing a voltage on a blanking capacitor, the voltage provided from a sensing node of a composite switching device via a blocking diode and a resistor, and detecting a short circuit condition based upon the sensed voltage.

A method of measuring self-Kerr in a physical quantum system configured to host a bosonic code qubit, comprises the following operations: 1) providing a physical quantum system configured to host a bosonic code qubit, said physical quantum system comprising (i) a quantum circuit comprising oscillators hosting a buffer or readout mode and a memory mode, and a non-linear element coupling the buffer or readout mode to the memory mode, and (ii) a control circuit configured to apply one or more control signals to the quantum circuit to stabilize the bosonic code qubit in the memory mode and further configured to receive measurement signals from at least the buffer or readout mode, 2) define a coherent state (α) for the memory mode, and, for each of a plurality of coherent state amplitudes and each of a plurality of durations (t), a. prepare, using the control circuit, said coherent state (α) in the memory having one of said plurality of coherent state amplitudes, b. wait for a period of time having one of said duration (t), c. apply, using the control circuit, one or more control signals to said quantum circuit such that the quantum circuit is in a resonant regime | i * ω a - ω b | = j * |ω cs | if said one or more control signals comprise an AC component having an angular frequency |ω cs | or | i * ω a - ω b | = 0 if said one or more control signals comprise only DC components, resulting in an interaction, mediated via said non-linear element, in said physical quantum system which results in a Hamiltonian having a leading term of the general formula Hi,(j,0) α ξ(j,0) (α†)i b + h.c...., where α is the annihilation operator of said memory mode, i is an integer superior or equal to 1, ω a is the angular frequency of the memory mode whilst the quantum circuit is in the resonant regime, j is an integer superior or equal to 1, b is the annihilation operator of the buffer or readout mode, ω b is the angular frequency of the buffer or readout mode whilst the quantum circuit is in the resonant regime, and ξ(j,0) is the strength of said interaction, and d. simultaneously to operation 2)c., using the control circuit, receiving measurement signals comprising at least the mode phase and / or mode amplitude of the buffer or readout mode, 3) derive an effective detuning or a decayed mode amplitude for each coherent state amplitude, by fitting of the measurements of operation 2)d. which are associated with said each coherent state amplitude, 4) derive at least one of self-Kerr coefficients, stark-shift detuning, and memory dephasing rate from the plurality of effective detunings or decayed mode amplitudes of operation 3) by fitting of a function of the absolute magnitude squares of coherent state amplitude in said memory mode.

Non-linear superconducting circuit for stabilizing at least one cat qubit, the non-linear superconducting circuit comprising: a four-wave mixing non-linear element (7); a first resonant portion (29); and a second resonant portion (31) which is coupled to the first resonant portion via the four-wave mixing non-linear element; wherein the first resonant portion, the second resonant portion, and the four-wave mixing non-linear element are configured together to provide a first physical oscillatory mode (a) with a first resonant frequency for hosting a cat qubit and a second physical oscillatory mode (b) with a second resonant frequency which is more dissipative than the first physical oscillatory mode (a); and wherein at least one of the first and second resonant portions comprises a tunable inductor (8) and a capacitor (43,39) such that at least one of the first and second resonant frequencies are tunable with the inductance of the tunable inductor.

An analog neural network is described comprising: a plurality of layers connected to form an electrical circuit having an input and an output, the input suitable for receiving an electrical signal corresponding to an input example and the output corresponding to an output of the neural network. Each layer comprises elements connected together, where the elements comprise: at least one programmable electronic element representing a weight of the neural network; at least one non-linear element; at least one amplifier block; an error element. Each layer also comprises a measurement element for measuring a change in an electrical signal across the error element.

There is provided a method for resetting an arbitrary state, hosted in a quantum system, to the vacuum Fock state or a coherent state, wherein the quantum system comprises: (I) at least one resonant portion configured to have a first mode having a first resonant frequency and wherein the arbitrary state is hosted in the first mode, (II) a non-linear element coupled to the at least one resonant portion so as to non-linearly couple to the first mode, and (III) one or more signal generator(s) coupled to the at least one resonant portion and / or to the non-linear element and configured to input control signals to physically stabilize a cat qubit subspace in the first mode having a cat phase angle. The method comprises: (i) physically stabilizing for a first period of time, with the one or more signal generator(s), a first cat qubit subspace having a first cat phase angle and first cat size ΙαΙ2, wherein α is a first amplitude which is the amplitude of the superposed coherent states Ι ± α > defining the first cat qubit subspace (702); (ii) after the first period of time, physically performing for a second period of time, with the one or more signal generator(s), a first parallel displacement drive by inputting electromagnetic radiation having a first phase substantially equal with the first cat phase angle, a frequency substantially equal to the first resonant frequency, and a first displacement amplitude greater than or equal to the first amplitude (704); (iii) after the second period of time, physically stabilizing for a third period of time, with the one or more signal generator(s), a second cat qubit subspace having a second cat phase angle which is substantially equal to the first cat phase angle and second cat size ΙβΙ2, wherein β is a second amplitude which is the amplitude of the superposed coherent states Ι ± β > defining the first cat qubit subspace, such that a coherent state Ιβ> with the second amplitude β is stabilized in the first mode (706). There is also provided a corresponding quantum processor, a computer program product, and a computer-readable medium.