Japan study reveals symmetry-controlled nonlinear effects in PV devices

A research team from Japan has demonstrated nonlinear photovoltaic effects in a heterostructure combining monolayer MoS₂ and layered CrPS₄. The system breaks both inversion and time-reversal symmetries, allowing the observation of a spontaneous shift current without applying external bias. This shift current, a key nonlinear photovoltaic response, was directly linked to the symmetry-breaking at the MoS₂/CrPS₄ interface. The magnitude of the photocurrent changed significantly based on the magnetic phase of the CrPS₄ layer, confirming its sensitivity to magnetic ordering. The study shows that combining materials with distinct inversion and rotational symmetries can produce controllable nonlinear photoresponses. These findings imply a novel route to the design of photovoltaic devices in which magnetic fields are used to modulate performance. The work points to the versatility of symmetry-engineered two-dimensional materials as a key to creating next-generation solar technologies.