I think the best, and also most popular, textbook for a Quantum Mechanics 1 course is "Introduction to Quantum Mechanics" by David J. Griffiths. This is also wh

I think the best, and also most popular, textbook for a Quantum Mechanics 1 course is "Introduction to Quantum Mechanics" by David J. Griffiths. This is also what Claude says. But you also need some math: Complex numbers, linear algebra, some basics of partial differential equations. But a traditional university course in quantum mechanics aims at doing quantum mechanics in 3-dimensional space, to solve electron orbitals and energy levels of hydrogen atom. But all this 3-dimensional mathematics, you don't necessarily need if you just want to read about quantum computers. Maybe some quantum computers textbook has a presentation of the basics of quantum mechanics that leaves out the topics that traditional physics needs, because traditionally physics was interested in how atoms are build.