Efficient and robust signal sensing by sequences of adiabatic chirped pulses

Abstract

We propose a scheme for sensing of an oscillating field in systems with large inhomogeneous broadening and driving field variation by applying sequences of phased, adiabatic, chirped pulses. These act as a double filter for dynamical decoupling, where the adiabatic changes of the mixing angle during the pulses rectify the signal and partially remove frequency noise. The sudden changes between the pulses act as instantaneous π pulses in the adiabatic basis for additional noise suppression. We also use the pulses' phases to correct for other errors, e.g., due to nonadiabatic couplings. Our technique improves significantly the coherence time in comparison to standard XY8 dynamical decoupling in realistic simulations in NV centers with large inhomogeneous broadening. Beyond the theoretical proposal, we also present proof-of-principle experimental results for quantum sensing of an oscillating field in NV centers in diamond, demonstrating superior performance compared to the standard technique.

Quantum optimal control using phase-modulated driving fields

“…Furthermore, our proposed method can be straightforwardly adapted and integrated to advanced and highly-developed optimization packages, e.g., Remote Dressed CRAB (RedCRAB), which is capable of performing closed-loop optimization remotely [79], and has been recently used to experimentally demonstrate the generation of genuine multipartite entanglement in the form of 20-qubit Greenberger-Horne-Zeilinger (GHZ) states with Rydberg atoms [80]. In addition, the capabilities to conveniently optimize gate robustness and prolong the coherence time using XY-8 sequences make the PM method potentially useful for improving the performance of DD techniques under inhomogeneous broadening [81] and quantum sensing experiments [78].…”

“…with τ and c being the noise relaxation time and the diffusion constant, respectively, and n representing a sample value of the unit normal distribution. We take noise parameters leading to a dephasing time of T * 2 ≈ 20 ns, that is τ = 20 µs, a standard deviation (cτ/2) 1/2 = 2π × 50 KHz for the dynamical noise while δ follows a Gaussian distribution with a zero mean value and a FWHM of 2π × 26.5 MHz for the static noise [78].…”

Optimal control of a nitrogen-vacancy spin ensemble in diamond for sensing in the pulsed domain

“…This consists of a substitutional nitrogen atom and an adjacent lattice vacancy, having discrete electronic and nuclear spin states with long coherence times up to room temperature. 3 The optical properties of the negativelycharged NV center (NV − ) are highly sensitive to a range of parameters including magnetic field [4][5][6][7][8][9] , electric field 5,10 , temperature 11,12 and pressure (strain). 13 Applications include sensing using a scanning diamond tip 14,15 , nanoscale nuclear magnetic resonance (NMR)/ electron spin resonance (ESR) 16,17 and in biophysics, [18][19][20][21] where robustness and high biocompatibility of diamond makes it an ideal platform for sensing, even within biological samples.…”

“…adiabatic chirped pulses. 8 . These are however unsuitable for applications that require DC to low frequency sensing, particularly for applications in biosensing 20,[46][47][48] .…”

Investigation and comparison of measurement schemes in the low frequency biosensing regime using solid-state defect centers

“…The level structure and spin-state dependent transitions of the NV center, illustrated in Fig. 1, render the system sensitive to temperature [8,9], pressure [10], electric fields [11,12] and magnetic fields [7], but it has received the most focus for its potential as a magnetometer [7,[13][14][15][16].…”