Time-Resolved Nanometer-Scale Temperature Sensing with Fluorescent Nanodiamonds
Pei-Chang Tsai1, Oliver Y. Chen1, Yan-Kai Tzeng1,2, Hsiou-Yuan Liu1,3, Hsiang Hsu1, Fu-Goul Yee3, Huan-Cheng Chang1,4, Ming-Shien Chang1*
1Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
2Department of Chemistry, National Taiwan University, Taipei, Taiwan
3Department of Physics, National Taiwan University, Taipei, Taiwan
4Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan
* presenting author:Ming-Shien Chang, email:msc@gate.sinica.edu.tw
Temperature sensing with nanoscale spatial resolution is gaining importance in many scientific and technological applications, ranging from bio-medical studies to heat dissipation in microelectronics devices. In this talk we present a time-resolved nanoscale luminescence thermometer utilizing 100-nm fluorescent nanodiamonds (FNDs). A three-point method at a sampling rate of 2.5 kHz for low-frequency noise rejection was developed, and temperature sensitivity of ~2K/√Hz with a working temperature range over ±100 K relative to a referenced ambient temperature was achieved. With the developed technique, time-resolved nanothermometry was demonstrated with 100-nm FNDs spin-coated on a glass substrate and submerged in gold nano-rod (GNR) solution heated by a near-infrared (NIR) laser, and nanoscale heat transfer with a temporal resolution of <10 μs was detected in a pump-probe type measurement. To validate the experimental data and to gain theoretical understanding, finite-element numerical simulation was also performed. Finally, we show that FNDs conjugated with GNRs are useful as a hybrid optical nanoheater and luminescence nanothermometer for highly localized hyperthermia treatment, and a temperature rise of ∼10 K can be readily achieved at a NIR laser power of 0.4 mW presented in cells. This technique is compatible with the presence of static magnetic fields, which allows simultaneous temperature and magnetic sensing with nanometric spatial resolution.

[1] Time-Resolved Luminescence Nanothermometry with Nitrogen-Vacancy Centers in Nanodiamonds, Nano Lett., 15, 3945−3952 (2015).
[2] Gold/diamond nanohybrids for quantum sensing applications, The EPJ Quantum Technology. 2:19, 1-12 (2015).

Keywords: diamond nanoparticle, color center, electron spin resonance, gold nanorod, time-resolved thermometry