One-Wave Optical Phase Conjugation Mirror by Actively Coupling Arbitrary Light Fields into a Single-Mode Reflector

Rewinding the arrow of time via phase conjugation is an intriguing phenomenon made possible by the wave property of light. Here, we demonstrate the realization of a one-wave optical phase conjugation mirror using a spatial light modulator. An adaptable single-mode filter is created, and a phase-conjugate beam is then prepared by reverse propagation through this filter. Our method is simple, alignment free, and fast while allowing high power throughput in the time-reversed wave, which has not been simultaneously demonstrated before. Using our method, we demonstrate high throughput full-field light delivery through highly scattering biological tissue and multimode fibers, even for quantum dot fluorescence.

Figure 1

Mirrors as optical systems. (a) Natural mirror system. (b) The ideal PCM system requires single light input $E_{in}$. (c) Conventional PCMs require additional reference beams $R$ and $R^{*}$. (d) Proposed idea utilizing a wave front shaper and a single-mode reflector.

Figure 2

Principle of the one-wave phase conjugation mirror. (a) For the initial optical system $\mathbf{S}$, the input light $|\psi ⟩$ is scrambled and the light is randomly distributed over multiple channels. (b) The reflected light from the single-mode channel $|a^{*}⟩$ will generate another randomly distributed output. (c) For the optimized optical system $\mathbf{S}$, the SLM actively couples arbitrary input fields into the single-mode channel. (d) In this case, the reflected single mode emitter would time reverse the incoming pathway.

Figure 3

Suppression of multiple scattering using the phase conjugation mirror. (a) Schematic of the optical setup. Red arrows represent the input wave front; dotted purple arrows represent the time-reversed wave front. SLM denotes the spatial light modulator. (b) Scattering media: ground glass (120 grit, displayed for the comparison), 2.8-mm-thickness tissue phantom, and 3.3-mm-thickness chicken breast tissue. (c),(h) Input images. Initial scrambled field images by (d),(i) tissue phantom and (f),(k) chicken breast tissue. Reconstructed images created behind (e),(j) tissue phantom, and (g),(l) chicken breast tissue.

Figure 4

Demonstration of various PCM applications. (a),(e) Schematic of the optical setups for delivering images through the MMF, and for QD fluorescence phase conjugation through scattering media, respectively. Note that the symbolized units (“O” and “$\mathrm{\Phi }$”) are identical to those in Fig. 3. (b),(f) Input field images. Scale bar: $30\mu \mathrm{m}$ and $5\mu \mathrm{m}$, respectively. (c),(g) Initial scrambled images. (d),(h) Reconstructed images.