Physicists demonstrate quantum mechanical nature of heat flow

Apr 15, 2005

One of the hallmarks of quantum mechanics -- the laws of physics that apply on very small scales -- is the wave nature exhibited by sub-atomic particles such as electrons. An electron presented with two paths to a destination will use its wave nature to traverse both paths and, depending on the parameters of the two paths, will constructively or destructively interfere with itself at its destination, leading to a high or low probability of it appearing there.

A classic demonstration of this is the Aharonov-Bohm effect where electrons are sent along two paths that may be altered by the application of an external magnetic field. By tuning the magnetic field, the constructive or destructive interference of the electrons is manifested as an increase or decrease in the conduction of electric current. Now physicists at Northwestern University show that, using the fact that electrons carry heat as well as charge, the conduction of heat may be similarly tuned. Their findings will be published April 22 by Physical Review Letters, the journal of the American Physical Society.

Venkat Chandrasekhar, professor of physics in Northwestern's Weinberg College of Arts and Sciences, and his graduate student Zhigang Jiang showed that a magnetic field can be used to increase or decrease the flow of heat through an "Andreev interferometer," a nanoscale device with one normal metal path and one superconducting path. Though the quantum interference of electrons in this device is responsible for these changes in heat flow, the flow of charge through the interferometer is zero. The researchers recently observed this effect experimentally.

Source: Northwestern University

Explore further: Researchers develop ultrahigh-resolution 3D microscopy technique for electric fields

Related Stories

Counting people with WiFi

Jun 08, 2015

Researchers in UC Santa Barbara professor Yasamin Mostofi's lab are proving that wireless signals can do more than provide Internet access. They have demonstrated that a WiFi signal can be used to count the ...

How to make continuous rolls of graphene

May 21, 2015

Graphene is a material with a host of potential applications, including in flexible light sources, solar panels that could be integrated into windows, and membranes to desalinate and purify water. But all ...

Recommended for you

Study reveals new method to develop more efficient drugs

16 hours ago

A new study led by University of Kentucky researchers suggests a new approach to develop highly-potent drugs which could overcome current shortcomings of low drug efficacy and multi-drug resistance in the ...

Tiny wires could provide a big energy boost

18 hours ago

Wearable electronic devices for health and fitness monitoring are a rapidly growing area of consumer electronics; one of their biggest limitations is the capacity of their tiny batteries to deliver enough ...

Graphene sheets enable ultrasound transmitters

18 hours ago

University of California, Berkeley, physicists have used graphene to build lightweight ultrasonic loudspeakers and microphones, enabling people to mimic bats or dolphins' ability to use sound to communicate ...

Could black phosphorus be the next silicon?

20 hours ago

As scientists continue to hunt for a material that will make it possible to pack more transistors on a chip, new research from McGill University and Université de Montréal adds to evidence that black phosphorus ...

Project uses crowd computing to improve water filtration

Jul 06, 2015

Nearly 800 million people worldwide don't have access to safe drinking water, and some 2.5 billion people live in precariously unsanitary conditions, according to the Centers for Disease Control and Prevention. ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.