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arXiv · 2412.08318

Ultrafast valleytronic logic operations

Francesco Gucci·Eduardo B. Molinero·Mattia Russo·Pablo San-Jose·Franco V. A. Camargo·Margherita Maiuri·Misha Ivanov·Álvaro Jiménez-Galán·Rui E. F. Silva·Stefano Dal Conte·Giulio Cerullo
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Abstract

Information processing currently reaches speeds as high as 800 GHz. However, the underlying transistor technology is quickly approaching its fundamental limits and further progress requires a disruptive approach. One such path is to manipulate quantum properties of solids, such as the valley degree of freedom, with ultrashort controlled lightwaves. Here we employ a sequence of few-optical-cycle visible pulses controlled with attosecond precision to excite and switch the valley pseudospin in a 2D semiconductor. We show that a pair of pulses separated in time with linear orthogonal polarizations can induce a valley-selective population. Additionally, exploiting a four-pump excitation protocol, we perform logic operations such as valley de-excitation and re-excitation at room temperature at rates as high as ~10 THz.

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Francesco Gucci, Eduardo B. Molinero, Mattia Russo, Pablo San-Jose, Franco V. A. Camargo, Margherita Maiuri, Misha Ivanov, Álvaro Jiménez-Galán, Rui E. F. Silva, Stefano Dal Conte, Giulio Cerullo. 2024-12-11. Ultrafast valleytronic logic operations. https://arxiv.org/abs/2412.08318

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