According to a news release from the National Institute of Standards and Technology (NIST), physicists at the NIST have "entangled" a microscopic mechanical drum with electrical signals.
The finding proves that NIST's micro-drum could be utilized as a quantum memory in future quantum computers, which would implement the rules of quantum physics to resolve issues that are difficult today. The research also signals the first-ever entanglement of a macroscopic oscillator, amplifying the range of realistic applications of the drum.
Entanglement is an interesting feature of the quantum world once thought to take place only at atomic and tinier scales. More recently, however, physicists have been discovering it in bigger systems. According to physicists, entanglement has technological applications. For example, it is important for quantum computing operations like fixing errors, and for quantum teleportation of data from one location to another.
In 2011, NIST made known the existence of the aluminum micro-drum and earlier this year implied it may have the capability to store data in quantum computers. The drum, which is only 15 micrometers in diameter and 100 nanometers thick, has both mechanical features and quantum properties.
The micro-drum is a component of an electromechanical circuit that can trade certain quantum states between the waveform of a microwave pulse and vibration in the drum. In the most recent test, a microwave signal "cooled" the drum to an extremely low energy level, only one unit of vibration, in a way similar to some laser-cooling methods. Then another signal forced the drum's motion to become entangled with a microwave pulse that arose spontaneously in the system.
The drum kept the quantum information in vibration energy for at least 10 microseconds, which is long enough to be beneficial in tests. Then the same kind of microwave signal that cooled the drum was utilized to move the state stored in the drum to a second microwave pulse.
Physicists determined the properties of the two microwave pulses and discovered that the findings were strongly correlated over 10,000 repetitions of the test. According to physicists, proof of quantum entanglement can found from the fact that determining the first microwave pulse gave physicists the ability to predict that features of the second pulse with better accuracy than would under other conditions be anticipated. The correlations between the two pulses suggested that the first pulse was entangled with the drum and the second pulse encoded the drum's state.
Besides its promise as a quantum memory tool, the micro-drum could also be utilized to produce entanglement in microwaves, to change one type of quantum information to an otherwise incompatible type.
The study's findings are described in detail in the journal Science Express.
