Simulation uses quantum mechanics to understand nanoelectronics

July 07, 1999

CHAMPAIGN, Ill. -- A computer simulation developed at the University of Illinois is helping scientists better understand the strange world of nanoelectronics -- where a single electron can control a device, but quantum mechanics is required to describe the behavior of that electron.

"We have simulated the operation of a silicon quantum-dot, floating-gate flash memory device," said Jean-Pierre Leburton, a U. of I. professor of electrical and computer engineering and a researcher at the university's Beckman Institute for Advanced Science and Technology. "The simulation can be used to explore and enhance the physical characteristics in future commercial devices."

Small, fast and rugged, flash memories can serve as temporary data storage in portable computers and cellular phones, and are key elements in digital imaging. They will eventually replace conventional magnetic storage media, Leburton said. "As fabrication technology continues to improve, the floating gates in flash memories may be reduced to nanometer-size structures that behave like quantum dots."

But as devices shrink to nanometer proportions, classical theory breaks down and quantum mechanics takes over. "You come to a point where things have become so small, you can identify the effects of a single electron charge with its wave-like behavior," Leburton said.

This "single-electron effect" reflects the granularity of matter in the nanoelectronic world. Not only must electrical current be understood as discrete particles governed by quantum mechanics (instead of millions of electrons flowing like a fluid); the physical composition of the device itself also must be taken into consideration.

"For example, the conductivity of a semiconductor is changed during manufacture by doping the material with impurities," Leburton said. "In the past, this doped material could be treated as a uniformly distributed background. Now, because of the incredibly small size, the characteristics of the device will change depending upon where atomic impurities are located."

To more thoroughly study the behavior of nanoelectronic devices, Leburton and graduate student Aaron Thean developed special simulation software. Their code consists of a three-dimensional, self-consistent solver with the necessary quantum mechanics to capture both the granularity of matter and the wave nature of the electron.

"In our simulation, you can see the wave-particle duality of the electron," Leburton said. "On one hand you see the granularity of matter due to the presence of a single, charged particle. On the other hand you see the wave nature of the electron, manifested in the form of additional capacitances."

By taking both of these effects into consideration, the computer simulation can help scientists and engineers design and optimize the performance of the next generation of nanoscale electronic devices.

The researchers discuss their simulation in the June issue of IEEE Electron Device Letters.
-end-


University of Illinois at Urbana-Champaign

Related Quantum Mechanics Articles from Brightsurf:

Theoreticians show which quantum systems are suitable for quantum simulations
A joint research group led by Prof. Jens Eisert of Freie Universit├Ąt Berlin and Helmholtz-Zentrum Berlin (HZB) has shown a way to simulate the quantum physical properties of complex solid state systems.

A new interpretation of quantum mechanics suggests reality does not depend on the measurer
For 100 years scientists have disagreed on how to interpret quantum mechanics.

New evidence for quantum fluctuations near a quantum critical point in a superconductor
A study has found evidence for quantum fluctuations near a quantum critical point in a superconductor.

Simulating quantum 'time travel' disproves butterfly effect in quantum realm
Using a quantum computer to simulate time travel, researchers have demonstrated that, in the quantum realm, there is no 'butterfly effect.' In the research, information--qubits, or quantum bits--'time travel' into the simulated past.

Orbital engineering of quantum confinement in high-Al-content AlGaN quantum well
Recently, professor Kang's group focus on the limitation of quantum confine band offset model, the hole states delocalization in high-Al-content AlGaN quantum well are understood in terms of orbital intercoupling.

A Metal-like Quantum Gas: A pathbreaking platform for quantum simulation
Coherent and ultrafast laser excitation creates an exotic matter phase with spatially overlapping electronic wave-functions under nanometric control in an artificial micro-crystal of ultracold atoms.

Fluid mechanics mystery solved
An environmental engineering professor has solved a decades-old mystery regarding the behavior of fluids, a field of study with widespread medical, industrial and environmental applications.

Quantum leap: Photon discovery is a major step toward at-scale quantum technologies
A team of physicists at the University of Bristol has developed the first integrated photon source with the potential to deliver large-scale quantum photonics.

USTC realizes the first quantum-entangling-measurements-enhanced quantum orienteering
Researchers enhanced the performance of quantum orienteering with entangling measurements via photonic quantum walks.

A convex-optimization-based quantum process tomography method for reconstructing quantum channels
Researchers from SJTU have developed a convex-optimization-based quantum process tomography method for reconstructing quantum channels, and have shown the validity to seawater channels and general channels, enabling a more precise and robust estimation of the elements of the process matrix with less demands on preliminary resources.

Read More: Quantum Mechanics News and Quantum Mechanics Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.