Optical thermometry based on level anticrossing in silicon carbide.

A N Anisimov,V Dyakonov,G V Astakhov,S P Lebedev,V A Soltamov,P G Baranov,D Simin

doi:10.1038/srep33301

Abstract

We report a giant thermal shift of 2.1 MHz/K related to the excited-state zero-field splitting in the silicon vacancy centers in 4H silicon carbide. It is obtained from the indirect observation of the optically detected magnetic resonance in the excited state using the ground state as an ancilla. Alternatively, relative variations of the zero-field splitting for small temperature differences can be detected without application of radiofrequency fields, by simply monitoring the photoluminescence intensity in the vicinity of the level anticrossing. This effect results in an all-optical thermometry technique with temperature sensitivity of 100 mK/Hz1/2 for a detection volume of approximately 10−6 mm3. In contrast, the zero-field splitting in the ground state does not reveal detectable temperature shift. Using these properties, an integrated magnetic field and temperature sensor can be implemented on the same center.

Highlights

We report a giant thermal shift of 2.1 MHz/K related to the excited-state zero-field splitting in the silicon vacancy centers in 4H silicon carbide
Using quantum-mechanical properties of the nitrogen-vacancy (NV) in diamond, the temperature sensitivity better than δT = 10 mK/Hz1/2 is achievable[3,10,11,12]. It is based on the moderate thermal shift dν0/dT = −7 4 kHz/K13,14 of the optically detected magnetic resonance (ODMR) frequency in the NV center (ν0 = 2.87 GHz at T = 300 K) and the use of the advanced readout protocols, temperature-scanned ODMR15 or thermal spin echo[10,11]
The realization of highly-sensitive and RF-free optical thermometry is of broad interest

Summary

Introduction

We report a giant thermal shift of 2.1 MHz/K related to the excited-state zero-field splitting in the silicon vacancy centers in 4H silicon carbide. It is based on the moderate thermal shift dν0/dT = −7 4 kHz/K13,14 of the optically detected magnetic resonance (ODMR) frequency in the NV center (ν0 = 2.87 GHz at T = 300 K) and the use of the advanced readout protocols, temperature-scanned ODMR15 or thermal spin echo[10,11].

Results

Conclusion