According to some Greek sources, Persia used slaves during around 330 BC. However, didn't Cyrus the Great abolish slavery? What was the status of slavery in the Person Empire (500-330 BC)?
The definition of slavery in this question would included people who were purchased as property for economic output, forced into military service without pay, as well as eunuchs acting as members of the royal court.
This thread has some discussion from myself and /u/Aithiopika on slavery in the Achaemenid Empire through a particular case, with links to another discussion as well.
The short of it is that. no, Cyrus did not abolish slavery, but slavery doesn't seem to have been integral to the socioeconomics of most of the Achaemenid Empire the way it was in, say, Rome, with perhaps the exception of Babylonian "labourers". Apart from that, bond-servants and servants on wealthy estates with various unclear social statuses was certainly a thing, as was forced labour with compensation.