Quantum

We study quantum entanglement, quantum imaging, and atomic physics. Entangled photons exhibit nonclassical characteristics and can be used for quantum imaging. Unlike classical optical imaging, quantum imaging has achieved sub-shot noise and super-resolution beyond the diffraction limit through coincidence detection. As photons originate from atoms/molecules, we also investigate atomic physics at the interface between classical and quantum physics. For example, we surprisedly found that the Bloch equation conventionally thought as classical only yields the von Neumann equation and the Schrödinger equation for spin-half particles. We also developed a theory that models the multi-stage Stern-Gerlach experiment suggested by Heisenberg and Einstein more accurately than the available theory.

Nov 2024, Optics & Photonics News: Enhancing Optical Microscopy with Quantum Entanglement

Drawing on the unique properties of entangled photons, quantum approaches can overcome the limitations of classical methods, enhance spatial resolution and reduce stray light and shot noise... More>>

Mar 2024, Caltech: Using Polarization to Improve Quantum Imaging

Quantum imaging is a growing field that takes advantage of the counterintuitive and "spooky" ability of light particles, or photons, to become linked, or entangled, under specialized circumstances... More>>

May, 2023 Caltech: Quantum Entanglement of Photons Doubles Microscope Resolution

Using a "spooky" phenomenon of quantum physics, Caltech researchers have discovered a way to double the resolution of light microscopes... More>>

Apr, 2023 Discover Magazine: Quantum Imaging Doubles Microscope Resolution

When it comes to quantum technologies, computing has dominated headlines around the world. Computers that exploit the laws of quantum mechanics are significantly faster for several classes of problem than even the most powerful supercomputers... More>>

1. Wang, L. V.; "Geometric interpretation of the hyperfine Breit–Rabi solution," ArXiv preprint arXiv:2509.12191 (2025) [PDF]
   
2. Wang, L. V.; "Deriving the von Neumann equation from the Majorana–Bloch equation for arbitrary spin in any state," ArXiv preprint arXiv:2508.08414 (2025) [PDF]
   
3. [Mostafaeipour, F.; Kahraman, S.; Titimbo, K.]; Tan, Y.; Wang, L. V.; "Simulation of atom trajectories in the original Stern–Gerlach experiment," Physica Scripta 100 045410 (2025) [PDF]
   
4. [Kahraman, S. S.; Titimbo, K.]; He, Z.; Shen, J.-T.; Wang, L. V.; "Quantum mechanical modeling of the multi-stage Stern–Gerlach experiment conducted by Frisch and Segrè," New Journal of Physics 26 073005 (2024) [PDF]
   
5. [He, Z.; Titimbo, K.; Garrett, D. C.]; Kahraman, S. S.; Wang, L. V.; "Numerical modeling of the multi-stage Stern–Gerlach experiment by Frisch and Segrè using co-quantum dynamics via the Schrödinger equation," Journal of Physics B: Atomic, Molecular and Optical Physics 56(20) 205005 (2023) [PDF]
   
6. [Titimbo, K.; Garrett, D. C.; Kahraman, S. S.; He, Z.]; Wang, L. V.; "Numerical modeling of the multi-stage Stern–Gerlach experiment by Frisch and Segrè using co-quantum dynamics via the Bloch equation," Journal of Physics B: Atomic, Molecular and Optical Physics 56(20) 205004 (2023) [PDF]
   
7. Wang, L. V.; "Multi-stage Stern–Gerlach experiment modeled," Journal of Physics B: Atomic, Molecular and Optical Physics 56(10) 105001 (2023) [PDF]; supplemental: arXiv:2208.06471 [PDF]
   
8. Wang, L. V.; "Derivation from Bloch equation to von Neumann equation to Schrödinger–Pauli equation," Foundations of Physics 52(3) 61 (2022) [PDF]; supplemental: arXiv:2407.08025 [PDF]

1. [He, Z.; Zhang, Y.; Tong, X.]; Li, L.; Wang, L. V.; "Heisenberg Scaling Quantum Microscopy: Experiment and Theory," ArXiv preprint arXiv:2303.04948 (2025) [PDF]
   
2. [Zhang, Y.; He, Z.; Tong, X.]; Garrett, D. C.; Cao, R.; Wang, L. V.; "Quantum imaging of biological organisms through spatial and polarization entanglement," Science Advances 10(10) (2024) [PDF]
   
3. [He, Z.; Zhang, Y.; Tong, X.]; Li, L.; Wang, L. V.; "Quantum microscopy of cells at the Heisenberg limit," Nature Communications 14(1) 2441 (2023) [PDF]
   
4. [Tong, X.; He, Z.; Zhang, Y.]; Solomon, S.; Lin, L.; Song, Q.; Wang, L. V.; "Experimental full-domain mapping of quantum correlation in Clauser-Horne-Shimony-Holt scenarios," Physical Review Applied 19(3) 034049 (2023) [PDF]