On-chip information technologies are primarily restricted to two-level systems due to a lack of sufficient reconfigurability to meet the demanding requirement, despite the rapid growth of photonic devices and systems. Even with significant efforts made to extend dimensionalities using newly developed vector lasers and microcavities, it is still difficult to actively manipulate the varied, high-dimensional superposition states of light on demand.
A spin-orbit microlaser chip developed by researchers at Penn Engineering surpasses the security and durability of current quantum communications equipment. Their approach doubles the quantum information space of earlier on-chip lasers by using “qudits” for communication.
Qubits, which are digital informational units capable of simultaneously being 1 and 0, are used in advanced quantum electronics. Superposition is the term used to describe this simultaneity in quantum physics. To indicate these extra dimensions, a quantum bit in a superposition state with more than two levels is referred to as a qudit.
According to Liang Feng, a professor at the Materials Science and Engineering (MSE) departments, “There is a lot of worry that mathematical encryption, no matter how complex, will become less and less effective since we are developing computing capabilities so quickly. Quantum communication is resistant to these upcoming dangers because it relies on physical barriers rather than mathematical ones. We must keep developing and improving quantum communication technology now more than ever.