论文标题
使用超导镉砷的拓扑表面状态解析检测器的微波光子数量
Microwave Photon Number Resolving Detector Using the Topological Surface State of Superconducting Cadmium Arsenide
论文作者
论文摘要
光子数分辨探测器在量子光学元件中起着核心作用。在微波频率范围内解决吸收光子的数量的一个关键挑战是找到合适的材料，不仅提供了吸收低能光子的适当频带结构，而且还提供了一种检测离散光电子激发的手段。为此，我们建议使用超导型砷化镉（CD3AS2）以拓扑半金属表面状态作为检测器来测量温度升高。表面电子吸收传入的光子，然后通过热量将多余的能量传递到超导大体的声子模式中。可以通过测量零偏置的大量电阻率的变化来确定温度增益，这不会显着影响晶格动力学。此外，获得的温度增益与吸收光子的数量离散化，从而实现了光子数分辨率的函数。在这里，我们将根据吸收光子的数量和频率来计算温度升高。我们还将从表面电子到散装声子的传热过程得出时间尺度。我们将特别表明转移过程足够快，可以忽略散热损失。
Photon number resolving detectors play a central role in quantum optics. A key challenge in resolving the number of absorbed photons in the microwave frequency range is finding a suitable material that provides not only an appropriate band structure for absorbing low-energy photons but also a means of detecting a discrete photoelectron excitation. To this end, we propose to measure the temperature gain after absorbing a photon using superconducting cadmium arsenide (Cd3As2) with a topological semimetallic surface state as the detector. The surface electrons absorb the incoming photons and then transfer the excess energy via heat to the superconducting bulk's phonon modes. The temperature gain can be determined by measuring the change in the zero-bias bulk resistivity, which does not significantly affect the lattice dynamics. Moreover, the obtained temperature gain scales discretely with the number of absorbed photons, enabling a photon-number resolving function. Here, we will calculate the temperature increase as a function of the number and frequency of photons absorbed. We will also derive the timescale for the heat transfer process from the surface electrons to the bulk phonons. We will specifically show that the transfer processes are fast enough to ignore heat dissipation loss.
