Semiconductor Quantum Electromechanical Structures

其中一个重要的成果是实现了基于半导体异质结构的片上微机械参量谐振器。我们提出的应用程序的基本设备的纳米机械参数计算机，并演示了一位操作。由于微/纳米机械谐振器中的能量耗散非常小，因此纳米机械参数计算机可以是高功率效率的数字处理系统。我们还成功地证明了这种参量谐振器可以用于参量信号放大和非常灵敏的电荷传感器。这也是一个非常重要的结果，基于微机械谐振器的振动阻尼控制的载流子激励。目前的阻尼控制都是通过微机械谐振器与光腔的耦合来实现的，这需要光学系统的精确对准。在我们的新方法中，通过激光波长调节进行微调，我们发现， ...更多信息 可以在带隙波长附近获得T效应。这表明这种效应是由载流子激发引起的，压电效应起着重要作用。通过使有效阻尼为负，成功地实现了机械悬臂梁的自振，并利用弛豫的In_（0.1）Ga_（0.9）As/In_（0.1）Al_（0.9）As缓冲层制备了微机械梁谐振器。施加拉伸应变后，基阶模态的固有频率增加。此外，对于最佳样品，获得了近一个数量级的更尖锐的共振线形状。该技术可广泛应用于改善基于谐振器的微/纳机电器件的性能，我们还发展了半导体机电器件的制造和测量技术，包括三维纳米光刻、嵌段共聚物光刻、量子点电学、纳米探针技术、半导体纳米线生长等。虽然它们不能与机电系统集成，但它们对未来量子机电系统的详细研究很有希望。少

One of the meet important results we obtained is the realization of on-chip micromechanical parametric resonator based on semiconductor heterostructures. We proposed the application to the basic device for a nanomechanical parametron computer and demonstrated one bit operation. Because the energy dissipation in the micro/nanomechanical resonator is extremely small, the nanomechanical parametron computer can be a highly power-efficient digital processing system. We also successfully demonstrate this parametric resonator can be used for parametric signal amplification and very sensitive charge sensors.It is also a very important result that the vibration damping in semiconductor-based micromechanical resonator was controlled by carrier excitation. So far the damping control was performed by coupling the micromechanical resonator to optical cavity, which needs fine alignment of optics. In our new method, the fine tuning was made by laser wavelength adjustment, and we found that significan … More t effects can be obtained at around the band gap wavelength. This indicates that the effect was caused by the carrier excitation and piezoelectric effects play important role. By making the effective damping negative, we also successfully realized self oscillation of mechanical cantilever.Furthermore, the Micromechanical beam resonators were fabricated using a strained film grown on a relaxed In_0.1Ga_0.9As/In_0.1Al_0.9As buffer layers. The natural frequency of fundamental mode was increased by the applied tensile strain. In addition, nearly one-order of magnitude sharper resonance line shape was obtained for the best sample. This technique can be widely applied for improving the performance of resonator-based micro/nanoelectromechamcal devices.We also made development of fabrication and measurement technique for semiconductor electromechanical devices, including 3D nanohthography, block co-polymer lithography, quantum dot electrometiy, nanoprobe technique, semiconductor nanowire growth. Although, they could not be integrated with electromechanical systems, they are promising for future detailed study of quantum electromechanical systems. Less