Single-electron thermal noise

Manipulation of random telegraph signals in a silicon nanowire transistor with a triple gate

Manipulation of carrier densities at the single electron level is inevitable in modern silicon based transistors to ensure reliable circuit operation with sufficiently low threshold-voltage variations. However, previous methods required statistical analysis to identify devices which exhibit random telegraph signals (RTSs), caused by trapping and de-trapping of a single electron. Here, we show that we can deliberately introduce an RTS in a silicon nanowire transistor, with its probability distribution perfectly controlled by a triple gate. A quantum dot (QD) was electrically defined in a silicon nanowire transistor with a triple gate, and an RTS was observed when two barrier gates were negatively biased to form potential barriers, while the entire nanowire channel was weakly inverted by the top gate. We could successfully derive the energy levels in the QD from the quantum mechanical probability distributions and the average lifetimes of RTSs. This study reveals that we can manipulate individual electrons electrically, even at room temperature, and paves the way to use a charged state for quantum technologies in the future.

Power generator driven by Maxwell's demon

Maxwell's demon is an imaginary entity that reduces the entropy of a system and generates free energy in the system. About 150 years after its proposal, theoretical studies explained the physical validity of Maxwell's demon in the context of information thermodynamics, and there have been successful experimental demonstrations of energy generation by the demon. The demon's next task is to convert the generated free energy to work that acts on the surroundings. Here, we demonstrate that Maxwell's demon can generate and output electric current and power with individual randomly moving electrons in small transistors. Real-time monitoring of electron motion shows that two transistors functioning as gates that control an electron's trajectory so that an electron moves directionally. A numerical calculation reveals that power generation is increased by miniaturizing the room in which the electrons are partitioned. These results suggest that evolving transistor-miniaturization technology can increase the demon's power output.

The study of Maxwell's demon provides a link between information thermodynamics and modern electronics. Using integrated nanometer-scale transistors in a single electron box configuration, Chida et al., demonstrate the extraction of electrical power by Maxwell's demon.

Sensing of single electrons using micro and nano technologies: a review

During the last three decades, the remarkable dynamic features of microelectromechanical systems (MEMS) and nanoelectromechanical systems (NEMS), and advances in solid-state electronics hold much potential for the fabrication of extremely sensitive charge sensors. These sensors have a broad range of applications, such as those involving the measurement of ionization radiation, detection of bio-analyte and aerosol particles, mass spectrometry, scanning tunneling microscopy, and quantum computation. Designing charge sensors (also known as charge electrometers) for electrometry is deemed significant because of the sensitivity and resolution issues in the range of micro- and nano-scales. This article reviews the development of state-of-the-art micro- and nano-charge sensors, and discusses their technological challenges for practical implementation.