Showing posts with label Noise. Show all posts
Showing posts with label Noise. Show all posts

Thursday, November 18, 2010

International workshop on Noise in Non-Equilibrium Systems: From Physics to Biology

Recent advances in the study of artificial and biological nano-systems have revealed that these two topics have in common more fundamental physical aspects than one would expect from the vastly different compositions, structures and functions of these systems. The prevalent strong interaction of the functional parts of both types of systems with their respective environments impose strong fluctuations and therefore most often render standard theoretical approaches like weak coupling theories inadequate. The functional aspects of artificial as well as biological systems generally rely on non-equilibrium conditions which may be imposed by chemical or electrical potential differences, or also by temperature differences. A time dependent external driving exhibits yet another non-equilibrium scenario.
The investigation of transport properties of charges, heat, or particles under strong non-equilibrium conditions in the presence of strong noise has been rich in surprising results and continues to present a lively field of research. While the relevance of quantum mechanics for charge transport in artificial nano-systems is well established, and also recent experiments with nano-mechanical systems have approached the quantum regime, the role of quantum mechanics for biological systems is still controversial.

The purpose of the workshop is to bring together leading experts from different topical research areas such as biophysics, quantum mechanics of nano-systems and transport processes, and to provide a stimulating scientific environment. It is our hope that the interactions among the participants will contribute to a deeper understanding of the fundamental role of noise.

View the original article here

International workshop on Noise in Non-Equilibrium Systems: From Physics to Biology

Recent advances in the study of artificial and biological nano-systems have revealed that these two topics have in common more fundamental physical aspects than one would expect from the vastly different compositions, structures and functions of these systems. The prevalent strong interaction of the functional parts of both types of systems with their respective environments impose strong fluctuations and therefore most often render standard theoretical approaches like weak coupling theories inadequate. The functional aspects of artificial as well as biological systems generally rely on non-equilibrium conditions which may be imposed by chemical or electrical potential differences, or also by temperature differences. A time dependent external driving exhibits yet another non-equilibrium scenario.
The investigation of transport properties of charges, heat, or particles under strong non-equilibrium conditions in the presence of strong noise has been rich in surprising results and continues to present a lively field of research. While the relevance of quantum mechanics for charge transport in artificial nano-systems is well established, and also recent experiments with nano-mechanical systems have approached the quantum regime, the role of quantum mechanics for biological systems is still controversial.

The purpose of the workshop is to bring together leading experts from different topical research areas such as biophysics, quantum mechanics of nano-systems and transport processes, and to provide a stimulating scientific environment. It is our hope that the interactions among the participants will contribute to a deeper understanding of the fundamental role of noise.

View the original article here

Friday, November 12, 2010

QCL Series Low Noise Quantum Cascade Laser Driver

The QCL Series Low Noise Drivers include patented circuitry ideal for driving Quantum Cascade Lasers (QCLs). Available in models up to 2A with low RMS noise (less than 0.7 µA for QCL1000).

An onboard Current Setpoint trimpot allows a DC bias to be set. Its signal sums with a remote Analog Input signal that can be negative or positive.

Safety: An onboard trimpot sets the current limit. Brownout, reverse voltage, and overvoltage protection isolate the QCL from power supply failures. An Overtemp Fault signal minimizes the chance of failure due to overheated electronics. Onboard or remote Enable controls when current can flow to the QCL. Once enabled, there is a 1.5 second delay and a slow-start ramp to safely power on the QCL. LED status indicators for Power ON, Enable, and FAULT are on the front panel. Status signals on the output connector can also drive external LEDs.

This OEM controller can be integrated into field deployed systems or used on a benchtop.

View the original article here