Sahih Bukhari Volume 9, Book 89, Hadith 6951

وَقَالَ اللَّيْثُ حَدَّثَنِي نَافِعٌ، أَنَّ صَفِيَّةَ ابْنَةَ أَبِي عُبَيْدٍ، أَخْبَرَتْهُ أَنَّ عَبْدًا مِنْ رَقِيقِ الإِمَارَةِ وَقَعَ عَلَى وَلِيدَةٍ مِنَ الْخُمُسِ، فَاسْتَكْرَهَهَا حَتَّى افْتَضَّهَا، فَجَلَدَهُ عُمَرُ الْحَدَّ وَنَفَاهُ، وَلَمْ يَجْلِدِ الْوَلِيدَةَ مِنْ أَجْلِ أَنَّهُ اسْتَكْرَهَهَا‏.‏ قَالَ الزُّهْرِيُّ فِي الأَمَةِ الْبِكْرِ، يَفْتَرِعُهَا الْحُرُّ، يُقِيمُ ذَلِكَ الْحَكَمُ مِنَ الأَمَةِ الْعَذْرَاءِ بِقَدْرِ قِيمَتِهَا، وَيُجْلَدُ، وَلَيْسَ فِي الأَمَةِ الثَّيِّبِ فِي قَضَاءِ الأَئِمَّةِ غُرْمٌ، وَلَكِنْ عَلَيْهِ الْحَدُّ‏.‏

And Safiyya bint Ubaid said:"A governmental male-slave tried to seduce a slave-girl from the Khumus of the war booty till he deflowered her by force against her will; therefore Umar flogged him according to the law he exiled him but he did not flogged the female slave because the male slave had committed illegal sexual intercourse by frce, against her will." Az-Zuhri said regarding a virgin slave-girl raped by a free man: the judge has to find the adulterer as much money as is equal to the price of the female slave and the adulterer has to be flogged (according to the islamic law);But if the slave woman is a matron, then, according to the verdict of the Imam, the adulterer is not fined but he has to recieve the legal punishment (according to islamic law).