Quantum Transistor with NV Charge Stabilization and Wavelength Tuning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Practical quantum computing devices based on Nitrogen Vacancy (NV) defects in diamond face challenges such as low quantum efficiency, spectral diffusion, and charge stability issues, which hinder the development of stable and efficient multi-qubit devices.
Innovation Solution
A quantum transistor device is designed with an optical resonator containing a crystal defect, such as an NV center in diamond, where electrodes apply electric fields to control the charge state and emission wavelength, coupled with optical waveguides for excitation and detection, and a semiconductor donor layer to create a PIN structure for precise voltage control, enhancing quantum efficiency and spectral calibration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If NV defects are used for qubit operations, then quantum computing capability is achieved, but charge stability deteriorates due to transitions between NV0 and NV- states
Solution Approach 1:
A gate electrode is introduced as an intermediary element between the environment and the NV defect. This gate electrode applies a transverse electric field that stabilizes the NV- charge state by creating an energy barrier against charge transitions, thereby maintaining charge stability while preserving quantum computing capability
Solution Approach 2:
The patent changes the electric field parameter by applying a controlled transverse electric field through the gate electrode. This parameter change modifies the energy landscape of the NV defect, stabilizing the desired NV- charge state and preventing transitions to NV0, thus resolving the charge stability issue
2Temperature
If crystal defects are used in solid-state materials, then compact qubits operating at room temperature are achieved, but spectral diffusion occurs causing frequency instability
Solution Approach 1:
The gate electrode serves as a mediator that applies a controlled electric field to compensate for spectral diffusion effects. By tuning the gate voltage, the emission wavelength can be stabilized, maintaining frequency reliability while operating at room temperature in solid-state diamond material
3Measurement precision
If optical excitation is applied to NV- centers, then spin polarization is achieved, but nonradiative losses reduce quantum efficiency
Solution Approach 1:
The optical resonator acts as an intermediary that enhances the radiative emission channel through Purcell effect. By coupling the NV- center to the resonator mode, the emission rate is enhanced and directed into the radiative channel, reducing nonradiative losses and improving quantum efficiency while maintaining spin polarization capability
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution increases quantum efficiency, stabilizes charge states, and calibrates spectral frequencies, enabling reliable multi-qubit operations and entanglement by maintaining the NV center in the NV− state during computations and tuning emission wavelengths to offset spectral diffusion.
Implementation Method 1
an optical resonator having a resonant wavelength band. A crystalline material including a crystal defect is contained within the optical resonator. The crystal defect has a ground state and an excited state, which has an emission wavelength in the resonant wavelength band
Implementation Method 2
A source electrode and a drain electrode are disposed on opposing sides of the crystal defect and configured to apply a first electric field in the crystalline material along a longitudinal axis
Implementation Method 3
A gate electrode is disposed in proximity to the crystal defect and configured to apply to the crystalline material a second electric field transverse to the longitudinal axis. Control circuitry is configured to apply a second voltage to the gate electrode to tune the emission wavelength
Implementation Method 4
Optical excitation of the NV− color center results in red photoluminescent emission, due to the transition between the 3E to the 3A2 triplet electronic states, with a zero-phonon line (ZPL) wavelength of approximately 637 nm
Implementation Method 5
The diamond crystal is configured as an optical waveguide, which is coupled to convey one or more excitation beams to the crystal defect
Data Source
AI summary
A quantum computing device includes an optical resonator having a resonant wavelength band. A crystalline material including a crystal defect is contained within the optical resonator. The crystal defect has a ground state and an excited state, which has an emission wavelength in the resonant wavelength band. A source electrode and a drain electrode are disposed on opposing sides of the crystal defect and configured to apply a first electric field in the crystalline material along a longitudinal axis. A gate electrode is disposed in proximity to the crystal defect and configured to apply to the crystalline material a second electric field transverse to the longitudinal axis. Control circuitry is configured to apply a first voltage between the source and drain electrodes to control a charge state of the crystal defect and to apply a second voltage to the gate electrode to tune the emission wavelength.