How can I specify "not_analyzed" for a specific nested object in my document?

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1

If I have a mapping like this:

{
  mappings: {
    'my_index': {
		properties: {
			i_want_analyzed: {
			  index: "my_analyzer",
			  properties {
			    some_field: {
				  type: 'string'
				}
			  }
			},
			i_do_not_want_analyzed: {
			  index: "not_analyzed",
			  properties {
			    some_other_field: {
				  type: 'string'
				}
			  }				
			}
		}
	}

Why does this not work? How can I make it so that non-explicit fields that get added under the "i_do_not_want_analyzed" will automatically be "not_analyzed", where fields added under "i_want_analyzed" will not get that behavior?