Discovery of 'hidden' quantum order improves prospects for quantum super computers

To measure the quantum order through this classically disordered liquid, scientists used neutrons to image the magnetic excitations – also called “flips” – and the distances over which they could propagate. The experiments were performed at the National Institute of Standards and Technology Center for Neutron Research in the United States and at the ISIS particle accelerator of the Rutherford Appleton Laboratory in the United Kingdom.

The team found that, despite the apparent classical disorder, magnetic excitations could propagate over long distances – up to 30 nanometers – at low temperature. (A nanometer is a billionth of a meter.)

The team members also discovered that they could limit coherence or make it disappear by introducing defects into the material through chemical impurities or heating. These defects “break the chains” into independent subchains, each with its own hidden order. This part of the research is the first step toward engineered spin-based quantum states in ceramics.

“Apart from the sheer beauty and mystique of quantum order beyond the atomic scale, there are very exciting prospects for applications in quantum computing to dramatically speed a wide range of computing that our society relies upon,” Broholm said.

Collaborators on this research include Guangyong Xu of Johns Hopkins and the U.S. Department of Energy’s Brookhaven National Laboratory; Broholm, Ying Chen, and Michel Kenzelmann of Johns Hopkins and the NIST Center for Neutron Research; Yeong-Ah Soh of Dartmouth College; Gabriel Aeppli of the London Centre for Nanotechnology and University College London; John. F. DiTusa of Louisiana State University; Christopher D. Frost from the ISIS Facility, Rutherford Appleton Laboratory, U.K.; Toshimitsu Ito and Kunihiko Oka of the National Institute of Advanced Industrial Science and Technology (AIST), Japan; and Hidenori Takagi from AIST and University of Tokyo.

The work was funded by the Office of Basic Energy Sciences within the U.S. Department of Energy’s Office of Science, the National Science Foundation, the Wolfson-Royal Society (U.K.), and by the Basic Technologies program of the U.K. Research Councils.

PDF copies of the study are available by contacting Lisa De Nike at or by calling 443-287-9960.

Related Web site:
Collin Broholm: http://www.pha.jhu.edu/~broholm/homepage/