The Indian set the records right after a real scare in the second game on yesterday and displayed top form to win the first rapid game and then drawing the second easily as white.
The victory means Harika will not only remain in the championship but will also have a fair chance of having a shy at the title with just two matches to go in the premier women event.
In the next round now, Harika will meet Antoaneta Stefanova of Bulgaria who was world champion in 2004.
Chinese Ju Wenjun defeated compatriot Hunag Qian, while Stefanova accounted for Marie Sebag of France in the other tiebreak matches.
In the other semifinal, Wenjun will meet Anna Ushenina of Ukraine who had won in straight games against Nadezhda Kosintseva of Russia.
Harika won with black in the first rapid game that proved to be the decisive factor in the match. Zhao Xue was the last fancied player remaining and she was knocked out in great style.
Taking a cue from her last game, Harika went for something she knows best instead of speculating. The King's Indian turned out to be a good choice as Zhao Xue could not get favourable complexities she was hoping for.
The middle game had all virtues of a typical King's Indian wherein black always had counter play against white's initiative.
Harika obtained a dangerous passed pawn in the center as the game progressed and took it to the seventh rank after Zhao blundered. The game lasted 33 moves.
In the return game, Harika faced the Hedgehog structure with white pieces and got a winning position in quick time. However, she played it safe for a long time and obtained the required draw after 85 moves.