From the Turkish tourism website
2 Types of the Turkish Tourist Visa
Turkish Single Entry Visa – The Turkish single entry visa allows foreigners to enter Turkey once. If foreign nationals leave the Turkish territory, then they need to obtain a separate visa to re-enter. This visa is valid for 3 months. And the requirements for this visa are the following:
i. original signed passport valid for six months;
ii. 1 blank visa page available for a visa stamp; and
iii. a copy of a 2×2 passport-type photograph.
Past experience has shown that regardless of what the embassy says the immigration authorities at the port of arrival can over rule and or void your visa and deport. You. Past experience has shown that there is a high probability of you being loaded back onto the same aircraft you arrived on!!!