I am bit confused why does YAMBO assumes time reversal symmetry in case of magnetic materials. It also detects time reversal symmetry when quantum espresso turns it off. Looking into a bit, I found that Yambo treats magnetic symmetries as time reversal symmetry( which I guess is not true as it enforces time reversal on ground state hamiltonian for all magnetic materials). Also it looks like QE and Yambo contradict with each other.
In q.e [source file PW/src/setup.f90][https://gitlab.com/QEF/q-e/-/blob/devel ... p.f90#L484]
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magnetic_sym = noncolin .AND. domag
time_reversal = .NOT. noinv .AND. .NOT. magnetic_sym
Where as in YAMBO [yambo/interfaces/int_modules/mod_com2y.F][https://github.com/yambo-code/yambo/blo ... om2y.F#L85]
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if(any(t_rev(:)==1)) then
mag_syms=.true.
i_time_rev=1
endif
To add a bit more, the SOC term respects time reversal symmetry, so hamilitoan respects time-reversal in non-magnetic SOC case. I also donot really understand the following line (I mean isn't just "n_spin_den==4" in the if condition?)
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if(l_spin_orbit.and.n_spin_den==4) i_time_rev=0
Best regards,
Murali