The spaser as a nanoscale quantum generator and ultrafast amplifier
The spaser as a nanoscale quantum generator and ultrafast amplifier
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DOI：
10.1088/2040-8978/12/2/024004
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发表时间：
2010-02-01
影响因子：
2.1
通讯作者：
Stockman, Mark I.
中科院分区：
文献类型：
--
作者：
Stockman, Mark I.
纳米等离子体激元学近年来得到了迅猛的发展，在基础理论和应用领域都取得了许多新的成果。spaser作为一种有源元件-相干局域场的产生器，已经被预言和实验观测到。如果spaser能作为一种超快纳米晶体管--一种MOSFET（金属氧化物半导体场效应晶体管）的光学对应物--发挥作用，将会取得更大的进展。一个令人生畏的问题是，spaser具有固有的反馈，导致纳米定位表面等离子体的量子产生和饱和，从而消除净增益，使其不适合放大。我们已经克服了这个固有的问题，并表明，spaser可以在两种模式下执行超快纳米放大器的功能：瞬态和瞬态。量子密度矩阵（光学布洛赫）方程的基础上，我们已经表明，spaser放大增益大于或接近50与开关时间小于或接近100 fs（潜在的，类似于10 fs）。这种有前景的spaser技术将进一步拓宽纳米科学的基础和应用领域，特别是使超快微处理器能够以10-100 THz的时钟速度工作。其他有前景的应用是超声波、超密度和超快信息存储以及生物医学。与半导体相比，Spasers基于金属，对电离辐射、高温、微波辐射和其他不利环境具有高抵抗力。
Nanoplasmonics has recently experienced explosive development with many novel ideas and dramatic achievements in both fundamentals and applications. The spaser has been predicted and observed experimentally as an active element-a generator of coherent local fields. Even greater progress will be achieved if the spaser can function as an ultrafast nanoamplifier-an optical counterpart of the MOSFET (metal-oxide-semiconductor field effect transistor). A formidable problem with this is that the spaser has inherent feedback, causing quantum generation of nanolocalized surface plasmons and saturation and consequent elimination of the net gain, making it unsuitable for amplification. We have overcome this inherent problem and shown that the spaser can perform functions of an ultrafast nanoamplifier in two modes: transient and bistable. On the basis of quantum density matrix (optical Bloch) equations we have shown that the spaser amplifies with gain greater than or similar to 50 with a switching time less than or similar to 100 fs (potentially, similar to 10 fs). This prospective spaser technology will further broaden both fundamental and applied horizons of nanoscience, in particular enabling ultrafast microprocessors working at 10-100 THz clock speed. Other prospective applications are in ultrasensing, ultradense and ultrafast information storage, and biomedicine. The spasers are based on metals and, in contrast to semiconductors, are highly resistive to ionizing radiation, high temperatures, microwave radiation, and other adverse environments.