VNU Journal of Science Mathematics – Physics, Vol 37, No 4 (2021) 59 67 59 Original Article Linear and Nonlinear Magneto optical Absorption Coefficients and Refractive Index Changes in Wse2 Monolayer Luong Van Tung1, Nguyen Quang Bau2, Tran Ngoc Bich3,4, Pham Tuan Vinh5, Huynh Vinh Phuc5,* 1Sai Gon University, 273 An Duong Vuong, Ho Chi Minh City, Vietnam 2VNU University of Science, 334 Thanh Xuan, Nguyen Trai, Hanoi, Vietnam 3University of Education, Hue University, 32 Le Loi, Hue City, Vietnam[.]