Diamond samples of defects with negative charged nitrogen-vacancy (NV) centers are promising solid state spin sensors suitable for quantum information processing, high sensitive measurements of magnetic, electric and thermal fields in nanoscale. The diamond defect with a NV center is unique for its robust temperature-dependent zero field splitting Dgs of the triplet ground state. This property enables optical readout of electron spin states through manipulation of the ground triplet state using microwave resonance with Dgs from 100 K to about 600 K. Thus, prohibiting Dgs from unwanted external thermal disturbances is crucial for an accurate measurement using diamond NV sensors. Our observation demonstrates the existence of a prominent microwave heating effect on the diamond samples of NV centers. The effect is inevitable to shift Dgs and cause measurement errors. The temperature increment caused by the effect monotonically depends on the power and the duration of microwave irradiation. The effect is obvious with the microwave irradiation in the continuous mode and some pulse sequence modes, but is neglectable for the quantum lock-in XY8-N method.
Quantum sensing has developed into a main branch of quantum science and technology. It aims at measuring physical quantities with high resolution, sensitivity, and dynamic range. Electron spins in diamond are powerful magnetic field sensors, but their sensitivity in the microwave regime is limited to a narrow band around their resonance frequency. Here, we realize broadband microwave detection using spins in diamond interfaced with a thin-film magnet. A pump field locally converts target microwave signals to the sensor-spin frequency via the non-linear spin-wave dynamics of the magnet. Two com…
Imaging of microwave magnetic field orientation using continuous-wave experiments on nitrogen-vacancy centers in diamond
Bennett University（贝内特大学）；IIT Madras（印度理工学院马德拉斯分校）；Center For Quantum Information, Communication And Computing, IIT Madras（印度理工学院马德拉斯分校量子信息、通信与计算中心）；Krea University（克雷亚大学）
13C dynamic nuclear polarization in diamond via a microwave-free 'integrated' cross effect
色心承载半导体正在成为在室温或接近室温下用于低场动态核极化（DNP）的有前途的源材料，但是超精细加宽、对磁场不均匀性的敏感性以及由其他顺磁缺陷引起的核自旋弛豫设置了难以规避的实际限制。在这里，我们探索了一种替代路线，色心辅助DNP使用氮空位（NV）中心的钻石耦合到替代氮杂质，所谓的P1中心。在水平反交叉条件附近工作-其中P1塞曼分裂匹配NV自旋跃迁之一-我们通过使用连续的磁场扫描和连续的光激发证明了有效的无微波13 C DNP。极化的幅度和符号可以通过调节每个周期中的低到高和高到低磁场扫描速率来控制，使得一个比另一个快得多。通过比较不同晶体取向的13 C DNP响应，我们表明该过程对磁场/NV未对准是稳健的，这一特征使得本技术适用于金刚石粉末和场不均匀的设置。应用于浅NV可以利用表面顺磁缺陷和外部核之间的更大物理接近性，以有效地包裹与金刚石晶体接触的目标样品。
Imaging of microwave field distribution over a non-fed gold pattern by using NV centers in diamond
金刚石中的氮空位中心已被广泛用作量子信息、磁学和微波场成像的平台。驱动NV中心的电子自旋所需的MW场的高精度空间控制对于这些应用是必不可少的。在这里，我们报告了一个控制MW场分布的钻石表面附近的微米级的金图案的激发。由平面环形MW天线激发的金图案充当接收天线并在局部区域中重新分布MW场，而无需直接馈送电流。平面环形微波天线在金刚石衬底上产生了一个面积为0.785 mm $^{2}$的均匀微波场，为检测微波变化提供了一个有用的工具。我们通过直接观察电子自旋拉比振荡对微米级金图案上的局部MW强度进行了成像，也显示了NV中心在MW场成像和MW器件表征中的潜在应用。我们实现了增强约19倍的Rabi频率在几微米的尺度上的黄金图案，相比，在存在的单个平面环MW天线的散装Rabi频率。与以前的方法相比，我们的方法已被证明是一个快速和简单的工具，在金刚石中的MW场的空间控制和NV中心的自旋操纵。
We theoretically study a strongly disordered superconducting layer heated by near-field microwave radiation from a nanometric metallic tip. The microwaves heat up the quasiparticles, which cool by phonon emission and conduction away from the heated area. Due to a bistability with two stable states of the electron temperature under the tip, the heating can be tuned to induce a submicrometer-sized normal region bounded by a sharp domain wall between high- and low-temperature states. We propose this as a local probe to access different physics from existing methods, for example, to map out inhomo…
In this paper cross-relaxation between nitrogen-vacancy (NV) centers and substitutional nitrogen in a diamond crystal was studied. It was demonstrated that optically detected magnetic resonance signals (ODMR) can be used to measure these signals successfully. The ODMR were detected at axial magnetic field values around 51.2~mT in a diamond sample with a relatively high (200~ppm) nitrogen concentration. We observed transitions that involve magnetic sublevels that are split by the hyperfine interaction. Microwaves in the frequency ranges from 1.3 GHz to 1.6 GHz ($m_S=0\longrightarrow m_S=-1$ NV …
Radiation-induced magnetotransport in high-mobility two-dimensional systems: Role of electron heating
本文用平衡方程方法分析了微波辐射对磁电阻的影响，该方法考虑了高迁移率二维系统中的朗道能级间和朗道能级内的过程，并考虑了光子辅助电子跃迁和辐射引起的电子分布变化。短程散射由于背景杂质和缺陷被证明是占主导地位的直接贡献者的光阻振荡。电子温度表征系统加热由于照射，通过平衡从辐射场的能量吸收和能量耗散到晶格通过现实的电子-声子耦合，表现出共振振荡。Shubnikov de Haas振荡幅度的微波调制与微波诱导的电阻振荡一起产生，与实验结果一致。此外，在较高的磁场侧的低频辐射引起的磁阻的抑制也被证明。
Transistors operating at high frequencies are the basic building blocks of millimeter-wave communication and sensor systems. The high velocity and mobility of carriers in graphene can open way for ultra-fast group IV transistors with similar or even better performance than can be achieved with III-V based semiconductors. However, the progress of high-speed graphene transistors has been hampered due to fabrication issues, influence of adjacent materials, and self-heating effects. Here, we report a graphene field-effect transistor (FET) on a diamond substrate, with a $f_{max}$ up to 54 GHz for a…
We introduce a double quantum (DQ) 4-Ramsey measurement protocol that enables wide-field magnetic imaging using nitrogen vacancy (NV) centers in diamond, with enhanced homogeneity of the magnetic sensitivity relative to conventional single quantum (SQ) techniques. The DQ 4-Ramsey protocol employs microwave-phase alternation across four consecutive Ramsey (4-Ramsey) measurements to isolate the desired DQ magnetic signal from any residual SQ signal induced by microwave pulse errors. In a demonstration experiment employing a 1-$μ$m-thick NV layer in a macroscopic diamond chip, the DQ 4-Ramsey pro…
Heating of black-Si by microwaves at 2.45 GHz: effect of nano-needle orientation
The Institute of Science Tokyo（东京科学大学）；Swinburne University of Technology（斯威本科技大学）；Melbourne Center for Nanofabrication (MCN)（墨尔本纳米制造中心）；Vilnius University（维尔纽斯大学）；Institute of Innovative Research, Institute of Science Tokyo（东京科学大学创新研究院）
CVD-growth of ultra-pure diamond, generation of NV centers by ion-implantation and their spectroscopic characterization for quantum technological applications
