Yes, the quantum erasure experiment has been conducted with interference, and it involves the storage of path information in qubits rather than classical bits. The experiment explores the concept of wave-particle duality and the role of measurement in quantum systems.
In a typical quantum erasure experiment, a particle (such as a photon) is sent through a double-slit apparatus. The double-slit apparatus consists of two narrow slits through which the particle can pass. When the particle passes through the slits, it exhibits wave-like interference patterns on a screen behind the slits.
However, if one tries to determine which path the particle took by placing detectors at the slits, the interference pattern disappears, and the particle behaves more like a classical particle that traveled through a specific slit. This is known as the "which-path" information, as it reveals the path the particle took through the slits.
In the quantum erasure experiment with interference, an additional step is introduced. After the particle passes through the double-slit apparatus, its path information is encoded into a qubit, which is typically a property of another quantum system called an ancilla.
The qubit can be entangled with the particle's path information, such that the state of the qubit corresponds to the "which-path" information. This entanglement destroys the interference pattern on the screen.
However, if the "which-path" information is subsequently erased or decohered by performing specific operations on the qubit, the interference pattern can be restored. This erasure of the path information is achieved by manipulating the qubit in such a way that the entanglement between the qubit and the particle's path becomes disentangled or no longer accessible.
By erasing the path information, the quantum system returns to a superposition of states, and the interference pattern reemerges on the screen.
These experiments illustrate the fundamental principles of quantum mechanics, the role of measurement, and the importance of preserving coherence in quantum systems. They highlight the unique properties of qubits and their potential applications in quantum information processing and communication.