Femtosecond laser written photonic and microfluidic circuits in diamond
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2019-03-04 |
| Journal | Journal of Physics Photonics |
| Authors | Vibhav Bharadwaj, Ottavia Jedrkiewicz, John P. Hadden, BelƩn Sotillo, Maria Ramos |
| Institutions | Politecnico di Milano, Universidad Complutense de Madrid |
| Citations | 73 |
Abstract
Section titled āAbstractāDiamond has attracted great interest in the quantum optics community thanks to its nitrogen vacancy \n(NV) center, a naturally occurring impurity that is responsiblefor the pink coloration of some diamond \ncrystals. The NV spin state with the brighter luminescence yield can be exploited for spin readout, \nexhibiting millisecond spin coherence times at ambient temperature. In addition, the energy levels of the \nground state triplet of the NV are sensitive to external fields. These properties make NVs attractive as a \nscalable platformfor efficient nanoscale resolution sensing based on electron spins and for quantum \ninformation systems. Integrated diamond photonics would be beneficial for optical magnetometry, due \nto the enhanced light-matter interaction and associated collection efficiency provided by waveguides, and \nfor quantum information, by means of the optical linking of NV centers for long-range entanglement. \nDiamond is also compellingfor microfluidic applications due to its outstanding biocompatibility, with \nsensingfunctionality provided by NV centers. Furthermore, laser written micrographitic modifications \ncould lead to efficient and compact detectors of high energy radiation in diamond. However, it remains a \nchallenge to fabricate optical waveguides, graphitic lines, NVs and microfluidics in diamond. In this \nReview, we describe a disruptive laser nanofabrication method based on femtosecond laser writing to \nrealize a 3D micro-nano device toolkitfor diamond. Femtosecond laser writing is advantageous \ncompared to other state of the art fabrication technologies due to its versatility in forming diverse micro \nand nanocomponents in diamond.We describe how high quality buried optical waveguides, low \nroughness microfluidic channels, and on-demand NVs with excellent spectral properties can be laser \nformed in single-crystal diamond.We show the first integrated quantum photonic circuit in diamond \nconsisting of an optically addressed NV for quantum information studies. The rapid progress of the field \nis encouraging but there are several challenges which must be met to realize future quantum technologies \nin diamond.We elucidate how these hurdles can be overcome using femtosecond laserfabrication, to \nrealize both quantum computing and nanoscale magnetic field sensing devices in synthetic diamond.