10 Jun Cool Computers
MADISON, WI.- A new nanoscale device developed by a University of Wisconsin-Madison Engineering professor could help dissipate heat generated by individual flowing electrons in such devices as laptop computers and provide insights into utilizing forces for quantum computing and communication. This device will allow researchers to study for the first time, in detail, the influence of heat dissipation on single electron transport in transistors.
Electrical and Computer Engineering Associate Professor Robert Blick collaborated on the work with graduate student, Eva Höhberger, as well as with professor Werner Wegscheider at the University of Regensburg, Germany, and researcher Tomas Krämer of Ludwig Maximilians University in Munich.
Blick and his colleagues developed something similar to a miniscule trampoline for bouncing individual electrons. It measures about 100 nanometers and operates as a suspended membrane suspended over a semiconductor cavity. The movement in the membrane is incredibly small, and the effects of heat dissipation will show up as vibrations of the suspended artificial atoms. This motion causes a change in voltage that researchers can measure.
The device vibrates in the gigahertz range whenever heat is dissipated inside quantum devices, causing a measurable voltage change. “When an electron spreads out as a wave, it has a scale of only about five nanometers, which is just the size scale we can address with our device,” said Blick.
The device itself is constructed of semiconductor materials and will serve as a prototype for future models. Lessons learned from this device could allow Engineers to further develop existing technology limited by the problem of heat dissipation. “The correlation between heat absorbed and the frequency of vibration of the suspended membrane could help future chip designers avoid generating excess heat,” said Blick.
Better understanding of heat dissipation will enable computer chip makers to bring down the temperature of intense heat-generating chips like central processing units (CPUs). “So much heat is being dissipated by CPUs today that may people’s laptops get uncomfortably warm. Our technique for studying low-dimensional electron systems should help future chips avoid generating so much heat,” said Blick.
“Heat is the number one killer of PC’s, so the cooler you can keep a computer or any electronic device the longer it will last,” said Jacob Biehl of Net-Pro Technology. “It’s a major limiting factor when they’re designing computer microprocessors – the faster the processor gets the more heat it generates. Keeping the heat down will enable faster processors to be built.
In a traditional computer, the presence of a group of electrons shows up as a negative charge and represents the “zero state” in binary logic, called a bit. When that charge is missing, the “one state” is represented. In contrast, a quantum computer deals with the quantum mechanics of electrons, which utilizes quantum bits or qubits. Unlike bits, qubits can exist in more than one state at once. This enables quantum computers to calculate all the possible solutions to a complex problem simultaneously, rather than running through them one-by-one like their binary counterparts.
Blick’s system, in the zero-dimension state, will allow researchers to observe an individual electron near the qubit level as it approaches the Heisenberg uncertainty principle. This principle states that as the location of a quantum mechanical particle is discovered, the direction of the particle cannot be calculated because any action to measure the particle changes the particle’s condition.
“Our technique advances the fundamental understanding of how individual electrons generate heat, and at the speed that chips are shrinking, in just two or three years semiconductor manufacturers are going to need the understanding that we are building up today,” said Blick.
Jamie Lyn Hofmeister is a freelance technology writer and regular contributor to the Wisconsin Technology Network. She can be reached at firstname.lastname@example.org.