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Light‐responsive materials enable the development of soft robots that are controlled remotely in 3D space and time without the need for cumbersome wires, onboard batteries, or altering the local environment. Azobenzene liquid crystal polymer networks are one such material that can move and deform in response to light actuation. Previous works have demonstrated azo‐based soft robotic grippers and transporters that are remotely powered by light. However, highly adaptive, automated spatiotemporal optical control over these materials has not yet been realized. Herein, a system for an azobenzene liquid crystal elastomer soft robotic arm is created by dynamically patterning light for independently maneuverable joints. The nonlinear material response to optical actuation is characterized, and the broad actuation space is explored with diverse arm configurations. A neural network is trained on the arm configurations and corresponding laser pattern to automate the pattern generation for a desired configuration. Finally, the azobenzene liquid crystal elastomer arm demonstrates complex targeted motion, marking an important step toward optically actuated soft robotics with applications ranging from optomechanics to biomedical tools. 

Abstract Photonics in the frequency range of 5–15 terahertz (THz) potentially open a new realm of quantum materials manipulation and biosensing. This range, sometimes called “the new terahertz gap”, is traditionally difficult to access due to prevalent phonon absorption bands in solids. Low‐loss phonon–polariton materials may realize sub‐wavelength, on‐chip photonic devices, but typically operate in mid‐infrared frequencies with narrow bandwidths and are difficult to manufacture on a large scale. Here, for the first time, quantum paraelectric SrTiO₃enables broadband surface phonon–polaritonic devices in 7–13 THz. As a proof of concept, polarization‐independent field concentrators are designed and fabricated to locally enhance intense, multicycle THz pulses by a factor of 6 and increase the spectral intensity by over 90 times. The time‐resolved electric field inside the concentrators is experimentally measured by THz‐field‐induced second harmonic generation. Illuminated by a table‐top light source, the average field reaches 0.5 GV m⁻¹over a large volume resolvable by far‐field optics. These results potentially enable scalable THz photonics with high breakdown fields made of various commercially available phonon–polariton crystals for studying driven phases in quantum materials and nonlinear molecular spectroscopy.