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Bulk ferromagnetism and large changes in photoluminescence intensity by magnetic field in $β$-Ga$_2$O$_3$

V. Sridharan·Sangam Banerjee·Manas Sardar·Sandip Dhara·N. Gayathri·V. S. Sastry
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Abstract

In this letter we report observation of room temperature ferromagnetism in bulk Ga$_2$O$_3$ . We also observe large (10-60%) increase/decrease in photoluminescence. In the red(700 nm wavelength)/blue(500 nm), with the application of small magnetic field(0.4 Tesla). We argue, that ferromagnetism occurs entirely due to chains of oxygen(O(3) sites, Fig. 5) vacancies. We propose a simple model to explain, origin and location of moment, formation of ferromagnetic dislocation needles, and strong increase/decrease ofred/blue photoluminescence intensity with magnetic field.

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V. Sridharan, Sangam Banerjee, Manas Sardar, Sandip Dhara, N. Gayathri, V. S. Sastry. 2007-01-11. Bulk ferromagnetism and large changes in photoluminescence intensity by magnetic field in $β$-Ga$_2$O$_3$. https://arxiv.org/abs/cond-mat/0701232

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