Opener's Rebid after Partner's Negative Double 11

Opener's Rebid after Partner's Negative Double 11

Question:

You are South. Matchpoints. None vul. 

You hold: 

KJ7642
KQ3
Q102
4

What is your next call on this auction:

  West    North    East    South  
   1spades icon
2hearts iconDbl Pass?

Answer: