Beyond the K-valley: exploring unique trion states in indirect band gap monolayer WSe2
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Abstract
Abstract We calculate the optical properties of monolayer WSe2 using ab initio many-body screened configuration interaction. For this indirect band gap material we describe additional species of negatively charged trions involving the Q-valley which are energetically more favorable than those formed at the K-valley. While the results are in excellent agreement with experimental data, they shed new light on observed but yet unaddressed optical features. The analysis of the many-body interactions reveals mechanisms behind increased singlet-triplet splitting and redshifted energies in these Q-valley trions, compared to K-valley trions.
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Research context
OpenAlex topics: 2D Materials and Applications · MXene and MAX Phase Materials · Graphene research and applications
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References (64)
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