High-precision measurements and first-principles explanation of the temperature-dependent <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mmultiscripts><mml:mi mathvariant="normal">C</mml:mi><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>13</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mmultiscripts><mml:mi mathvariant="normal">N</mml:mi><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>14</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow></mml:math> hyperfine interactions of single <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mrow><mml:mi>NV</mml:mi></mml:mrow><mml:mo>−</mml:mo></mml:msup></mml:math> centers in diamond at room temperature

Abstract

Revealing the properties of single spin defects in solids is essential for quantum applications based on solid-state systems. However, it is intractable to investigate the temperature-dependent properties of single defects, due to the low precision for single-defect measurements in contrast to defect ensembles. Here we report that the temperature dependence of the Hamiltonian parameters for single negatively charged nitrogen-vacancy centers in diamond at room temperature is precisely measured and the results are in reasonable agreement with first-principles calculations. In particular, the hyperfine interactions with randomly distributed $^{13}\mathrm{C}$ nuclear spins are clearly observed to vary with temperature and the relevant coefficients are measured with hertz-level precision. The temperature-dependent behaviors are attributed to both thermal expansion and lattice vibrations by first-principles calculations. Our results pave the way for taking nuclear spins as more stable thermometers at nanoscale. The methods developed here for high-precision measurements and first-principles calculations can be further extended to other solid-state spin defects.

Topics & Concepts