High temperature nv center sensing up to 1400k

A method for fast laser heating and cooling of nano/micro-diamonds (NDs) containing nitrogen-vacancy (NV) centers, comprising:

• optically polarizing NV center spins in the NDs;
• applying a pulse of near-infrared (NIR) laser light having a wavelength of approximately 850 nm and a duration of about 2000 nanoseconds to heat the NDs to a stationary elevated temperature;
• allowing the NDs to cool down to approximately room temperature after stopping the NIR laser pulse for spin readout;
• applying a microwave pulse of approximately 40 nanoseconds during at least one of the heating stage and the cooling stage;
• performing pulsed optically detected magnetic resonance (ODMR) measurements of the NDS during the heating and/or the cooling stages;
• analyzing the ODMR spectra obtained;
• and
• determining temperature-dependent zero-field splitting (D) of the resonance by Lorentzian fitting of the ODMR spectra.

A method for determining spin coherence in a nitrogen-vacancy (NV) center in nano- or micro-diamonds under fast laser heating and cooling, comprising:

• optically polarizing the NV center spins by a green laser pulse of approximately 5 microseconds;
• heating the nano- or micro-diamonds to a stable elevated temperature by a near-infrared (NIR) laser pulse of approximately 3.5 microseconds;
• applying a first microwave pulse of π/2 rotation to the NV center spins;
• maintaining the elevated temperature for a variable delay time t;
• applying a second microwave pulse of π/2 rotation;
• allowing the nano- or micro-diamond to cool;
• performing optical readout of spin states;
• and
• repeating the above steps with a modified sequence in which the first microwave pulse is replaced by a 3π/2 pulse.