By combining ab initio calculations and experiments, we demonstrate how the band gap of the transition metal trichalcogenide TiS3 can be modified by inducing tensile or compressive strain. In addition, using our calculations, we predicted that the material would exhibit a transition from a direct to an indirect band gap upon application of a compressive strain in the direction of easy electrical transport. The ability to control the band gap and its nature could have a significant impact on the use of TiS3 for optical applications. We go on to verify our prediction via optical absorption experiments that demonstrate a band gap increase of up to 9% (from 0.99 to 1.08 eV) upon application of tensile stress along the easy transport direction.

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通过从头算和实验相结合，我们证明了过渡金属三卤化钛TiS 3的带隙如何能够通过引起拉伸或压缩应变而改变。另外，使用我们的计算，我们预测，在沿易于电传输的方向施加压缩应变后，该材料将表现出从直接带隙到间接带隙的转变。控制带隙的能力及其性质可能会对TiS 3在光学应用中的使用产生重大影响。我们继续通过光吸收实验验证我们的预测，该实验表明，沿易传输方向施加拉应力后，带隙最多可增加9％（从0.99到1.08 eV）。

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