US 2019/0293425 A1 · GYROCOPE BASED ON NITROGEN VACANCY CENTERS IN DIAMOND

Abstract

The invention pertains to the field of gyroscopes, in particular—to quantum gyroscopes. The invention provides a gyroscope employing an ensemble of NV-centers in diamond, which includes a diamond plate, a source of green light, an optical system for directing the green light to the diamond plate, a photodetector for registering fluorescence of the color centers in the diamond plate, optical elements that direct the fluorescence from the diamond plate to the photodetector, a source of microwave radiation, a source of radiofrequency radiation, and a source of constant magnetic field, the gyroscope being different from the prior art in that it comprises an energy-efficient antenna that creates a strong longitudinal homogeneous field in the entire volume of the diamond plate with the possibility of frequency adjustment, as well as a system for locking the frequency of the microwave field to that of the transition in the color centers. The invention allows to reduce the volume of the sensing element, provides high relative spectral sensitivity, and allows to create a hybrid device that comprises a 3-axis gyroscope, a magnetometer, and a temperature sensor.

Claims11

Dependent claims

A gyroscope based on NV-centers in a diamond, comprising a diamond plate, a source of a green light, an optical system for directing the green light onto the diamond plate, a photodetector for registering fluorescence of the NV-centers in the diamond plate, optical elements directing the fluorescence from the diamond plate to the photodetector, a source of super-high-frequency radiation, a source of radio frequency radiation, and a source of constant magnetic field, wherein the gyroscope additionally comprises an energy-efficient antenna for microwaves that creates a strong longitudinal homogeneous microwave field in the entire volume of the diamond, is configured to provide a frequency adjustment of said microwave field, and configured to have a system for coupling the frequency of said microwave field to a frequency of the transition in the NV centers.

A method for measuring a rotation angle of a quantum sensor that comprises a diamond plate implanted with an ensemble of NV centers, said method comprises the following steps:

a. bringing the NV centers ensemble and surrounding nuclear spins into a rotation-sensitive state through N>1 cycles of population transfer from the states with the projection of the nuclear spin MI=±1 to those with MI=0, where each cycle includes the following sequence of pulses:
i. an optical pulse with the duration from 300 to 1500 ns to transfer the NV centers ensemble and surrounding nuclear spins into the state with MS=0, and a uniform distribution among MI=1, -1, and 0,
ii. a microwave n pulse to switch the system from the state with MS=0, MI=1 to the state with MS=+1, MI=1,
iii. a radiofrequency n pulse to transfer the system from the state with MS=+1, MI=1 to the state with MS=+1, MI=0,
iv. an optical pulse of incoherent excitation with the duration 300-1500 ns and the wavelength of 532 nm which preserves the nuclear spin state in the presence of an external magnetic field and transfers the system into the state with MS=0, MI=-1,
v. repeating steps ii-iv for the system in the state MS=0, MI=-1,
vi. repeating steps ii-v N times, where N is in the range 1-5000.
b. controlling the system during the rotation measurements, which includes the use of RF pulses to filter out external noise, reducing the influence of temperature and external magnetic field by measuring the electronic spin transitions with MS=−1 and MS=1, as well as measuring the magnetic field with a help of the diamond plate;
c. reading out an information about rotation by measuring the geometric Berry phase accumulated during rotation measurements, including the following steps:
i. application of a radiofrequency π/2 pulse at the frequency detuned by dF* from the hyperfine splitting frequency,
ii. measurement of the nuclear spin state by application of the CNOT gate to the electronic spin-nuclear spin system, for example, through the use of a microwave π/2 pulse at the electronic resonance frequency modified by the value of the hyperfine splitting,
iii. measurement of the fluorescence response intensity.

9 more elements

Dependencies are inferred from the claim text.

Gyrocope based on nitrogen vacancy centers in diamond

Life of this patent

Gyrocope based on nitrogen vacancy centers in diamond

Life of this patent

Abstract

Claims11