gistfile1.txt

{
  "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "serviceBusTopics": {
      "defaultValue": [
        {
          "name": "topic1",
          "subscriptions": [
            "topic1-sub1",
            "topic1-sub2"
          ]
        },
        {
          "name": "topic2",
          "subscriptions": [
            "topic2-subAbc"
          ]
        },
        {
          "name": "topicOther",
          "subscriptions": [
            "topicOther-subDef"
          ]
        }
      ],
      "type": "array"
    }
  },
  "resources": []
}