Nanomechanics has brought mesoscopic physics into the world of vibrations. Because nanomechanical systems are small, fluctuations are significant, the vibrations already become nonlinear for comparatively small amplitudes, and new mechanisms of dissipation come into play. At the same time, the exquisite control of these systems makes them a platform for studying many problems of classical and quantum physics far from thermal equilibrium in a well-characterized setting. This review describes, at a conceptual level, basic theoretical ideas and explicative experiments pertaining to mesoscopic physics of nanomechanical systems. Major applications of nanomechanics in science and technology are also outlined. A broad range of phenomena related to the conservative as well as dissipative nonlinearity and fluctuations are discussed within a unifying framework. They include the linear response of single and coupled vibrational modes as well as nonlinear effects of periodic driving. Such driving breaks the continuous time-translation symmetry and the detailed balance, with conspicuous consequences for fluctuations, particularly in the presence of the driving-induced bistability and multistability. Mathematical techniques are described in the appendixes to provide an introduction to the theory. The goal of the review is to show the richness of the physics at work. The continuous experimental and theoretical advances make nanomechanical systems a vibrant area of research with many new phenomena to discover.

中文翻译：

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纳米力学系统的介观物理

纳米力学将介观物理学带入振动世界。由于纳米力学系统很小，波动很大，振动对于相对较小的振幅来说已经变得非线性，并且新的耗散机制开始发挥作用。与此同时，对这些系统的精确控制使它们成为在充分表征的环境中研究远离热平衡的许多经典和量子物理问题的平台。这篇综述在概念层面上描述了与纳米机械系统介观物理相关的基本理论思想和解释性实验。还概述了纳米力学在科学技术中的主要应用。在统一的框架内讨论了与保守以及耗散非线性和波动相关的广泛现象。它们包括单一和耦合振动模式的线性响应以及周期性驱动的非线性效应。这种驱动打破了连续时间平移对称性和细节平衡，对波动产生明显的后果，特别是在存在驱动引起的双稳态和多稳态的情况下。附录中描述了数学技术，以提供对该理论的介绍。审查的目的是展示物理学的丰富性。不断的实验和理论进步使纳米机械系统成为一个充满活力的研究领域，有许多新现象有待发现。