Phoniton systems, devices, and methods
An artificial composite object combines a quantum of sound with a matter excitation. A phonon in a confinement structure containing the matter excites it from an initial state to an excited state corresponding to a frequency of the phonon. Relaxation of the matter back to the initial state emits a phonon of the same frequency into the confinement structure. The phonon confinement structure, for example, a cavity, traps the emitted phonon thereby allowing further excitation of the matter. The coupling between the phonon and the matter results in a quantum quasi-particle referred to as a phoniton. The phoniton can find application in a wide variety of quantum systems such as signal processing and communications devices, imaging and sensing, and information processing.
1. A method for producing a phoniton, the method comprising:
trapping a phonon in a cavity; and
coupling the trapped phonon to a quantum two-level system in the cavity, the quantum two-level system having a first energy state and a second energy state, the phonon being coupled such that a mode of the trapped phonon corresponds to a transition at or near a difference between the first and second energy states, the quantum two-level system being arranged at an anti-node or a node of the trapped phonon.
2. The method of claim 1 , wherein the quantum two-level system is a solid-state quantum two-level system.
3. The method of claim 1 , wherein the quantum two-level system comprises at least one of a donor, an acceptor, a color center, a defect, a quantum dot, a nanocrystal, or a colloidal quantum dot.
4. The method of claim 1 , wherein the coupling is such that a coupling rate between the trapped phonon mode and the two-level system is in the strong coupling regime.
5. The method of claim 4 , wherein the trapped phonon is coupled to the quantum two-level system such that the coupling energy between the phonon and the quantum two-level system is greater than losses of the two-level system and the phonon in the cavity.
6. The method of claim 1 , further comprising providing a crystalline-based device containing the quantum two-level system and the resonant cavity.
7. The method of claim 1 , wherein, prior to the trapping, the phonon is generated external to the resonant cavity and provided thereto.
8. The method of claim 1 , wherein, prior to the trapping, the phonon is generated by the two-level system using at least one of electrical generation, thermal generation, optical generation, or tunneling.
9. The method of claim 1 , further comprising altering at least one of the first and second energy states such that a transition amplitude or transition probability between them is changed.
10. The method of claim 9 , wherein the altering includes at least one of straining the material, applying an electric field, or applying a magnetic field.
11. The method of claim 1 , further comprising altering a resonant frequency of the cavity such that the phonon energy in the cavity does not correspond to a transition frequency at the difference between the first and second energy states.
12. The method of claim 1 , wherein the phonon has a frequency in the terahertz regime or lower.