A meditation on the fundamental trade-offs that define our understanding of nature’s deepest mysteries
Category: quantum physics – Page 16
A new way for quantum computing systems to keep their cool
Heat causes errors in the qubits that are the building blocks of a quantum computer, so quantum systems are typically kept inside refrigerators that keep the temperature just above absolute zero (−459 degrees Fahrenheit).
But quantum computers need to communicate with electronics outside the refrigerator, in a room-temperature environment. The metal cables that connect these electronics bring heat into the refrigerator, which has to work even harder and draw extra power to keep the system cold. Plus, more qubits require more cables, so the size of a quantum system is limited by how much heat the fridge can remove.
To overcome this challenge, an interdisciplinary team of MIT researchers has developed a wireless communication system that enables a quantum computer to send and receive data to and from electronics outside the refrigerator using high-speed terahertz waves.
(From 2023)
A new wireless terahertz communication system enables a super-cold quantum computer to send and receive data without generating too much error-causing heat.
Nonreciprocal light speed control achieved using cavity magnonics device
The reliable manipulation of the speed at which light travels through objects could have valuable implications for the development of various advanced technologies, including high-speed communication systems and quantum information processing devices. Conventional methods for manipulating the speed of light, such as techniques leveraging so-called electromagnetically induced transparency (EIT) effects, work by utilizing quantum interference effects in a medium, which can make it transparent to light beams and slow the speed of light through it.
Despite their advantages, these techniques only enable the reciprocal control of group velocity (i.e., the speed at which the envelope of a wave packet travels through a medium), meaning that a light beam will behave the same irrespective of the direction it is traveling in while passing through a device. Yet the nonreciprocal control of light speed could be equally valuable, particularly for the development of advanced devices that can benefit from allowing signals to travel in desired directions at the desired speed.
Researchers at the University of Manitoba in Canada and Lanzhou University in China recently demonstrated the nonreciprocal control of the speed of light using a cavity magnonics device, a system that couples microwave photons (i.e., quanta of microwave light) with magnons (i.e., quanta of the oscillations of electron spins in materials).
Quantum Enabled Radar
Advances in Quantum technologies offer a step improvement in phase noise performance compared to conventional oscillators. University of Birmingham (UoB) is developing a new class of ultra low phase noise optical lattice clock Quantum oscillator that can provide several orders of magnitude improvement in radar sensitivity against clutter.
To facilitate this enabling research, the Advanced Radar Network (ADRAN) facility funded by the EPSRC Quantum Technologies Hub is being set-up to enable comparative performance assessment of a radar systems with quantum oscillators as compared to conventional alternatives.
This may be shared as something else, but these guys just used quantum tech to “unstealth stealth”. I think that’s a pretty cool thing to accomplish.
Information about quantum enabled radar research in the Microwave Integrated Systems Laboratory (MISL) at the University of Birmingham.
Phase-resolved attoclock precisely measures electron tunneling time
When placed under a powerful laser field (i.e., under strong-field ionization), electrons can temporarily cross the so-called quantum tunneling barrier, an energy barrier that they would typically be unable to overcome. This quantum mechanics phenomenon, known as quantum tunneling, has been the focus of numerous research studies.
Precisely measuring the exact time that an electron spends inside a quantum tunneling barrier during strong-field ionization has so far proved challenging. In recent years, physicists have developed advanced experimental tools called attoclocks, which can measure the timing of ultrafast electron dynamics and could thus help to answer this long-standing research question.
Despite their potential for measuring the tunneling time of electrons, most attoclocks developed to date have had significant limitations and have been unable to yield reliable and conclusive measurements. In a recent paper published in Physical Review Letters, researchers at Wayne State University and Sorbonne University introduced a new attoclock technique that leverages the carrier-envelope phase (CEP), the offset between the peak of a laser’s pulse’s envelope and its oscillating field, to collect more precise tunneling time measurements.
Scientists discover extremely neutron-deficient isotope protactinium-210
Researchers from the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences and their collaborators have synthesized a new isotope—protactinium-210—for the first time. It is the most neutron-deficient isotope of protactinium synthesized to date. Their findings are published in Nature Communications.
The atomic nucleus is a quantum many-body system composed of protons and neutrons. Synthesizing and studying new nuclides is a frontier research topic in nuclear physics. Through this research, scientists can explore the limits of the existence of nuclei and deepen our understanding of the fundamental properties of matter.
Theoretical predictions suggest the existence of around 7,000 nuclides, yet only about 3,300 have been experimentally synthesized and observed so far.
