# US 11,910,728 B2 · Flopping-mode electric dipole spin resonance > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,910,728 B2 - Document ID: US11910728B2 - Status: Granted - Kind: B2 - Application number: 16/937,330 - Filed: 2020-07-23 - Published: 2021-01-28 - Granted: 2024-02-20 - Earliest claimed: 2019-07-23 - Assignees: The Trustees of Princeton University - Applicants: The Trustees of Princeton University - Inventors: Jason Petta; Stefan Putz; Xiao Mi - Web page: https://patentgrep.com/patent/US11910728B2 ## CPC - H10D 30/402: {Single electron transistors; Coulomb blockade transistors} - H10D 48/383: {Quantum effect devices, e.g. of devices using quantum reflection, diffraction or interference effects} - H10D 48/3835: {Semiconductor qubit devices comprising a plurality of quantum mechanically interacting semiconductor quantum dots, e.g. Loss-DiVincenzo spin qubits} - H10D 64/27: Electrodes not carrying the current to be rectified, amplified, oscillated or switched, e.g. gates - H10N 60/11: {Single-electron tunnelling devices} - B82Y 10/00: Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES ## Abstract Methods, devices, and systems are described for performing quantum operations. An example device at least one magnetic field source configured to supply an inhomogeneous magnetic field, at least one semiconducting layer, and one or more conducting layers configured to: define at least two quantum states in the at least one semiconducting layer, and cause, based on an oscillating electrical signal supplied by the one or more conducting layers, an electron to move back and forth between the at least two quantum states in the presence of the inhomogeneous magnetic field. The movement of the electron between the at least two quantum states may generate an oscillating magnetic field to drive a quantum transition between a spin-up state and spin-down state of the electron thereby implementing a qubit gate on a spin state of the electron. ## Claims ### Claim 1 A nanoscale semiconductor quantum device, comprising: at least one magnetic field source configured to supply an inhomogeneous magnetic field; at least one semiconducting layer; and one or more conducting layers comprising a source and a drain and configured to: define at least two quantum states in the at least one semiconducting layer; and cause, based on an oscillating electrical signal supplied by the one or more conducting layers, an electron to move back and forth between the at least two quantum states in the presence of the inhomogeneous magnetic field, wherein the movement of the electron between the at least two quantum states generates an oscillating magnetic field to drive a quantum transition between a spin-up state and spin-down state of the electron thereby implementing a qubit gate on a spin state of the electron, wherein the at least one magnetic field source is located in a first layer of a material stack of the device and the one or more conducting layers are located in a second layer, of the material stack, different from the first layer. ### Claim 2 (depends on 1) The device of claim 1, wherein the at least two quantum states comprise a gate defined silicon double quantum dot, and wherein the oscillating electrical signal has one or more of a microwave frequency, a radio frequency, or a frequency in a range of about 3 kHz to about 300 GHz. ### Claim 3 (depends on 1) The device of claim 1, wherein the at least one magnetic field source comprises at least one micro-magnet that is electrically isolated from the at least one semiconducting layer and the one or more conducting layers. ### Claim 4 (depends on 1) The device of claim 1, wherein the one or more conducting layers comprise a first conducting layer comprising one or more barrier gates configured to define the at least two quantum states, and wherein the one or more conducting layers comprise a second conducting layer comprising one or more plunger gates configured to cause the electron to move between the at least two quantum states. ### Claim 5 (depends on 1) The device of claim 1, wherein the one or more conducting layers comprise a first plunger gate configured to apply the oscillating electrical signal to move the electron between the at least two quantum states and a second plunger gate configured to electrically couple a charge of the electron to an electric field of a cavity for spin-state readout. ### Claim 6 (depends on 1) The device of claim 1, wherein the one or more conducting layers are configured to cause the electron to move back and forth based on simultaneously applying a microwave frequency burst and a square voltage pulse to a plunger gate of the one or more conducting layers thereby driving a coherent spin rotation within a specific rotation angle defined by a value of detuning set by the square voltage pulse. ### Claim 7 (depends on 1) The device of claim 1, wherein the at least two quantum states are biased to within a few micro-electron volts of zero detuning such that the at least two quantum states are on resonance. ### Claim 8 (depends on 1) The device of claim 1, wherein the inhomogeneous magnetic field extends into a portion of the at least one semiconducting layer in which the electron moves back and forth between the at least two quantum states. ### Claim 9 (depends on 1) The device of claim 1, wherein the at least one magnetic field source causes a magnetic field gradient sufficiently large to cause a change in the magnetic field, in a range of about 1 mT to about 1000 mT, as the electron moves between the at least two quantum states. ### Claim 10 A system for operating a nanoscale semiconductor quantum device, the system comprising: a signal generator configured to generate an oscillating electrical signal; and a structure disposed in a cavity, the structure comprising: at least one magnetic field source configured to supply an inhomogeneous magnetic field; at least one semiconducting layer; and one or more conducting layers comprising a source and a drain and configured to: define at least two quantum states in the at least one semiconducting layer; and cause, based on the oscillating electrical signal generated by the signal generator and supplied by the one or more conducting layers, an electron to move back and forth between the at least two quantum states in the presence of the inhomogeneous magnetic field, wherein the movement of the electron between the at least two quantum states generates an oscillating magnetic field to drive a quantum transition between a spin-up state and spin-down state of the electron thereby implementing a qubit gate on a spin state of the electron, wherein the at least one magnetic field source is located in a first layer of a material stack of the structure and the one or more conducting layers are located in a second layer, of the material stack, different from the first layer. ### Claim 11 (depends on 10) The system of claim 10, wherein the at least two quantum states comprise a gate defined silicon double quantum dot, and wherein the oscillating electrical signal has one or more of a microwave frequency, a radio frequency, or a frequency in a range of about 3 kHz to about 300 GHz. ### Claim 12 (depends on 10) The system of claim 10, wherein the at least one magnetic field source comprises at least one micro-magnet that is electrically isolated from the at least one semiconducting layer and the one or more conducting layers. ### Claim 13 (depends on 10) The system of claim 10, wherein the one or more conducting layers comprise a first conducting layer comprising one or more barrier gates configured to define the at least two quantum states, and wherein the one or more conducting layers comprise a second conducting layer comprising one or more plunger gates configured to cause the electron to move between the at least two quantum states. ### Claim 14 (depends on 10) The system of claim 10, wherein the one or more conducting layers comprise a first plunger gate configured to apply the oscillating electrical signal and a second plunger gate configured to electrically couple a charge of the electron to an electric field of the cavity. ### Claim 15 (depends on 10) The system of claim 10, wherein the one or more conducting layers are configured to cause the electron to move back and forth based on simultaneously applying a microwave frequency burst and a square voltage pulse, generated by the signal generator, to a plunger gate of the one or more conducting layers thereby driving a coherent spin rotation within a specific rotation angle defined by a value of detuning set by the square voltage pulse.