Robust High-Dynamic-Range Vector Magnetometry via Nitrogen-Vacancy Centers in Diamond

We demonstrate a robust, scale-factor-free vector magnetometer, which uses a closed-loop frequency-locking scheme to simultaneously track Zeeman-split resonance pairs of nitrogen-vacancy (NV) centers in diamond. Compared with open-loop methodologies, this technique is robust against fluctuations in temperature, resonance linewidth, and contrast; offers a three-order-of-magnitude increase in dynamic range; and allows for simultaneous interrogation of multiple transition frequencies. By directly detecting the resonance frequencies of NV centers aligned along each of the diamond's four tetrahedral crystallographic axes, we perform full vector reconstruction of an applied magnetic field

Nanophotonic Filters and Integrated Networks in Flexible 2D Polymer Photonic Crystals

Polymers have appealing optical, biochemical, and mechanical qualities, including broadband transparency, ease of functionalization, and biocompatibility. However, their low refractive indices have precluded wavelength-scale optical confinement and nanophotonic applications in polymers. Here, we introduce a suspended polymer photonic crystal (SPPC) architecture that enables the implementation of nanophotonic structures typically limited to high-index materials. Using the SPPC platform, we demonstrate nanophotonic band-edge filters, waveguides, and nanocavities featuring quality (Q) factors exceeding 2, 300 and mode volumes (Vmode) below 1.7(λ/n)3. The unprecedentedly high Q/Vmode ratio results in a spectrally selective enhancement of radiative transitions of embedded emitters via the cavity Purcell effect with an enhancement factor exceeding 100. Moreover, the SPPC architecture allows straightforward integration of nanophotonic networks, shown here by a waveguide-coupled cavity drop filter with sub-nanometer spectral resolution. The nanoscale optical confinement in polymer promises new applications ranging from optical communications to organic opto-electronics, and nanophotonic polymer sensors.National Basic Research Program of China (973 Program) (2012CB921900)United States. Dept. of Energy (Office of Basic Energy Sciences, Contract No. DE-AC02-98CH10886)National Science Foundation (U.S.) (NSF Award No. IIP-1152707)United States. Air Force Office of Scientific Research (PECASE, Presidential Early Career Award for Scientists and Engineers)United States. National Aeronautics and Space Administration (NASA Space Technology Research Fellowship

Diamond-nitrogen-vacancy electronic and nuclear spin-state anticrossings under weak transverse magnetic fields

We report on detailed studies of electronic and nuclear spin states in the diamond-nitrogen-vacancy (NV) center under weak transverse magnetic fields. We numerically predict and experimentally verify a previously unobserved NV hyperfine level anticrossing (LAC) occurring at bias fields of tens of gauss—two orders of magnitude lower than previously reported LACs at ∼ 500 and ∼ 1000 G axial magnetic fields. We then discuss how the NV ground-state Hamiltonian can be manipulated in this regime to tailor the NV's sensitivity to environmental factors and to map into the nuclear spin state.United States. Dept. of Defense. Assistant Secretary of Defense for Research & Engineering (Air Force Contract No. FA8721-05-C-0002)United States. Office of Naval Research (N00014-13-1-0316)United States. National Aeronautics and Space Administration ( Office of the Chief Technologist’s Space Technology Research Fellowship

High-sensitivity spin-based electrometry with an ensemble of nitrogen-vacancy centers in diamond

We demonstrate a spin-based, all-dielectric electrometer based on an ensemble of nitrogen-vacancy (NV[superscript −]) defects in diamond. An applied electric field causes energy-level shifts symmetrically away from the NV[superscript −]'s degenerate triplet states via the Stark effect; this symmetry provides immunity to temperature fluctuations allowing for shot-noise-limited detection. Using an ensemble of NV[superscript −]s, we demonstrate shot-noise-limited sensitivities approaching 1 (V/cm)/√Hz under ambient conditions, at low frequencies (<10 Hz), and over a large dynamic range (20 dB). A theoretical model for the ensemble of NV[superscript −]s fits well with measurements of the ground-state electric susceptibility parameter 〈k[subscript ⊥]〉. Implications of spin-based, dielectric sensors for micron-scale electric-field sensing are discussed.United States. National Aeronautics and Space Administration. Office of Chief Technologist (Space Technology Research Fellowship)United States. Air Force Office of Scientific Research. Presidential Early Career Award in Science and Engineerin

Sensing and timekeeping using a light-trapping diamond waveguide

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.Cataloged from PDF version of thesis.Includes bibliographical references (pages 103-112).Solid-state quantum systems have emerged as promising sensing platforms. In particular, the spin properties of nitrogen vacancy (NV) color centers in diamond make them outstanding sensors of magnetic fields, electric fields, and temperature under ambient conditions. This thesis focuses on spin-based sensing using multimode diamond waveguide structures to efficiently use large ensembles of NV centers (> 10¹⁰). Temperature-stabilized precision magnetometry, thermometry, and electrometry are discussed. In addition, the precision characterization of the NV ground state structure under a transverse magnetic field and the use of NV-diamond for spin-based clocks are reported.by Hannah Clevenson.Ph. D

Gas Sensing Using a Resilient Polymer Photonic Crystal Nanocavity with Ultra-High Quality Factor

We present a high-sensitivity, multi-use optical gas sensor based on a one-dimensional polymer photonic crystal cavity. With an experimental Q exceeding 13100, we predict detection levels on the parts-per-billion range for a variety of gases