I want to modulate from D major to B minor. I have a perfect cadence (A7 - D) in D major, after which I need to use a pivot chord to go into B minor. I was thinking of using the F# chord, but I am not sure if it should be an F#m or F#.
According to my knowledge, a pivot chord has to be common between the original key & the key you want to modulate into. If I have to use the F# chord, I would have to use A# as an accidental in the chord (since F# as a chord doesn't exist in D major). So should I use this chord, or simply write it as F#m? This means that the relative minor would have to be B natural minor. Is this ok?
Also, what other chords could be better ways of modulating into the relative minor? When modulations go into the minor, is it generally the harmonic minor which is used, or it depends according to accidentals (if any) are used?