arXiv subjects

D. A. Simpson

Publications and source records attributed to D. A. Simpson.

21 records · Page 2Linked to original sources

arXiv2009

Photophysics of novel diamond based single photon emitters

A detailed study of the photophysical properties of several novel color centers in chemical vapor deposition diamond is presented. These emitters show narrow luminescence lines in the near infra-red. Single photon emission was verified with continuous and pulsed excitation with emission rates at saturation in the MHz regime, whilst direct lifetime measurements reveal excited state lifetimes ranging from 1-14 ns. In addition, a number of quantum emitters demonstrate two level behavior with no bunching present in the second order correlation function. An improved method of evaluating the quantum efficiency through the direct measurement of the collection efficiency from two level emitters is presented and discussed. \

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arXiv2009

Nano-manipulation of diamond-based single photon sources

The ability to manipulate nano-particles at the nano-scale is critical for the development of active quantum systems. This paper presents a new technique to manipulate diamond nano-crystals at the nano-scale using a scanning electron microscope, nano-manipulator and custom tapered optical fibre probes. The manipulation of a ~ 300 nm diamond crystal, containing a single nitrogen-vacancy centre, onto the endface of an optical fibre is demonstrated. The emission properties of the single photon source post manipulation are in excellent agreement with those observed on the original substrate.

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arXiv2009

A highly efficient two level diamond based single photon source

An unexplored diamond defect centre which is found to emit stable single photons at a measured rate of 1.6 MHz at room temperature is reported. The novel centre, identified in chemical vapour deposition grown diamond crystals, exhibits a sharp zero phonon line at 734 nm with a full width at half maximum of ~ 4 nm. The photon statistics confirm the center is a single emitter and provides direct evidence of the first true two-level single quantum system in diamond.

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