Thin Circular Diamond Membrane with Embedded Nitrogen-Vacancy Centers for Hybrid Spin-Mechanical Quantum Systems

Abstract

Hybrid quantum systems (HQSs) have attracted several research interests in the last years. In this Letter, we report on the design, fabrication, and characterization of a novel diamond architecture for HQSs that consists of a high quality thin circular diamond membrane with embedded near-surface nitrogen-vacancy centers (NVCs). To demonstrate this architecture, we employed the NVCs by means of their optical and spin interfaces as nanosensors of the motion of the membrane under static pressure and in-resonance vibration, as well as the residual stress of the membrane. Driving the membrane at its fundamental resonance mode, we observed coupling of this vibrational mode to the spin of the NVCs by Hahn echo signal. Our realization of this architecture will enable futuristic HQS-based applications in diamond piezometry and vibrometry, as well as spin-mechanical and mechanically mediated spin-spin coupling in quantum information science. KEYWORDS: hybrid quantum systems, nitrogen-vacancy center, thin circular diamond membrane, harmonic oscillator, Hahn echoThere have been several recent proposals 1-2 to exploit mechanical degrees of freedom to control and couple nitrogen-vacancy centers (NVCs) for applications in quantum information science 1-4 and nano-force sensing [5][6] . For example, mechanical motions of diamond microcantilevers have been detected via the electronic spins of NVCs 7-9 . Such proposals rely on the incorporation of NVCs into well-characterized nano/micro-mechanical structures that behave according to simple models from continuum mechanics. However, the realization of such ideal structures, free from complications like residual stress, is a significant challenge yet to be achieved. Thus, a vital first step is to comprehensively characterize these factors and their influence on the performance of the structures. Furthermore, unlike other materials such as SiN 10 , the manufacturing of large, homogenous, and high-quality thin diamond membranes for the simple, robust and scalable fabrication of diamond nano/micro-mechanical structures is yet to be demonstrated.In this Letter, we report a novel approach to the systematic design, fabrication, and characterization of a circular diamond membrane (hereinafter will be mentioned shortly as "membrane") incorporating NVCs at the average depth of ≈20 nm. The membrane has a diameter of ≈1.1 mm, a thickness of ≈1.2 μm and surface roughness of ≈0.4 nm. To examine the mechanical properties of the membrane, we employed the confocal microscopy technique that uses the fluorescence point spread function (PSF) of individual embedded NVCs as nanosensors to measure the deflection of the membrane under an applied pressure. In this way, and by applying the theory of thin membranes 11 we have inferred an effective thickness of ≈1.2 µm and average radial residual stress of 54 MPa. By means of the spin-mechanical coupling of the NVCs, we employed them as nanoprobes for the motion of the membrane under applied static pressure (DC) and in-resonance vibration (AC), as we...

Optical imaging of localized chemical events using programmable diamond quantum nanosensors

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Robust and efficient quantum optimal control of spin probes in a complex (biological) environment. Towards sensing of fast temperature fluctuations

“…One representative of such quantum sensors, is the negatively charged nitrogen-vacancy center (NV) in diamond. Several applications as a magnetic [1] and electric field [2], pressure [3] and temperature [4][5][6][7][8][9][10][11][12] probe have been demonstrated. In addition, one can also extract chemical information about samples by nuclear magnetic resonance with ∼Hz spectral and nanometer-scale spatial resolution [13,14].…”

Новые Линии Люминесценции В Полученных Методом Химического Газофазного Осаждения Наноалмазах

“…Биосовместимость, химическая инерт-ность, низкая токсичность и возможность химической функционализации поверхности наноалмазов открыва-ет перспективу применения наноалмазов с центрами окраски для биомедицины [7]. В алмазных пленках и частицах, полученных методом химического газофазного осаждения (chemical vapor deposition-CVD), наиболь-ший интерес прикован к следующим центрам окраски: кремний−вакансия (SiV) [9][10][11][12][13][14][15][16][17][18][19][20], Ni-содержащим [21][22][23][24][25], Сr-содержащим [26][27][28], азот−вакансия (NV) [29,30]. Недавно в спектрах ФЛ в алмазе, полученном методом CVD, обнаружены узкие линии ФЛ [31][32][33], структура и механизм формирования которых остаются не до конца установленными.…”